feat(artist): editable display name + rename surface; drop name-uniqueness (#130 step 1)

First step of decoupling artist identity/storage/display. migration 0077 drops
uq_artist_name so the display name is free text (two genuinely different creators
can share a name); the slug stays the immutable, unique storage/identity key (the
on-disk path component — untouched, so nothing moves). ArtistService.rename +
PATCH /api/artists/<id> change the name ONLY. Frontend: inline pencil-edit on the
artist header (mirrors TagCard), slug/route unaffected so no navigation. Fixes the
operator's 'no surface to rename an artist' + the name-collision fragility.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CDgx8bQS5YrGRK76v8HUnM

alembic/versions/0077_artist_name_not_unique.py

@@ -0,0 +1,32 @@
+"""drop uq_artist_name — decouple display name from identity/storage
+
+Revision ID: 0077
+Revises: 0076
+Create Date: 2026-07-04
+
+Artist model fragility fix (milestone #130). One `slug` column was doing
+identity + storage-path + display, and BOTH `name` and `slug` were UNIQUE, so
+the display name couldn't be edited freely and two genuinely different creators
+collided. Decouple: `slug` stays the immutable, unique storage/identity key (the
+on-disk path component — untouched here); `name` becomes freely editable, NON-
+unique display text. This migration only drops the `uq_artist_name` constraint;
+no data moves and no path changes.
+"""
+from typing import Sequence, Union
+
+from alembic import op
+
+revision: str = "0077"
+down_revision: Union[str, None] = "0076"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    op.drop_constraint("uq_artist_name", "artist", type_="unique")
+
+
+def downgrade() -> None:
+    # Re-adding the UNIQUE would fail if duplicate names now exist; callers that
+    # need to reverse this must dedupe names first.
+    op.create_unique_constraint("uq_artist_name", "artist", ["name"])

backend/app/api/artists.py

@@ -31,6 +31,24 @@ async def create_or_get():
     }), 201
 
 
+@artists_bp.route("/<int:artist_id>", methods=["PATCH"])
+async def rename(artist_id: int):
+    """Rename an artist's DISPLAY NAME (#130). Name only — the slug and every
+    on-disk path stay put, so this is instant and safe. Name is non-unique."""
+    body = await request.get_json()
+    if not isinstance(body, dict) or not isinstance(body.get("name"), str):
+        return jsonify({"error": "invalid_body"}), 400
+    async with get_session() as session:
+        svc = ArtistService(session)
+        try:
+            artist = await svc.rename(artist_id, body["name"])
+        except ValueError as exc:
+            return jsonify({"error": "empty_name", "detail": str(exc)}), 400
+        if artist is None:
+            return jsonify({"error": "not_found"}), 404
+        return jsonify({"id": artist.id, "name": artist.name, "slug": artist.slug})
+
+
 @artists_bp.route("/autocomplete", methods=["GET"])
 async def autocomplete():
     q = request.args.get("q") or ""

backend/app/models/artist.py

@@ -15,7 +15,14 @@ class Artist(Base):
     __tablename__ = "artist"
 
     id: Mapped[int] = mapped_column(Integer, primary_key=True)
-    name: Mapped[str] = mapped_column(String(255), nullable=False, unique=True)
+    # Display name: freely editable, NON-unique (two real creators can share a
+    # name). Decoupled from identity/storage in migration 0077 (#130) — renaming
+    # touches ONLY this. Was unique until then.
+    name: Mapped[str] = mapped_column(String(255), nullable=False)
+    # Storage/identity key: IMMUTABLE + unique. This is the on-disk path
+    # component (download_service artist_slug = artist.slug → images_root/<slug>/
+    # <platform>/…), so it is set once at creation (collision-suffixed) and NEVER
+    # changes — a rename must not move files. Existing artists keep their slug.
     slug: Mapped[str] = mapped_column(String(255), nullable=False, unique=True)
     notes: Mapped[str | None] = mapped_column(Text, nullable=True)
 

backend/app/services/artist_service.py

@@ -283,6 +283,23 @@ class ArtistService:
             await self.session.commit()
         return artist, created
 
+    async def rename(self, artist_id: int, name: str) -> Artist | None:
+        """Change the display NAME only (#130). The slug — and every on-disk path
+        keyed off it — is IMMUTABLE, so a rename never moves files or risks a path
+        collision. Name is free text and NON-unique (migration 0077). Returns the
+        updated Artist, None if not found; raises ValueError on empty name."""
+        cleaned = (name or "").strip()
+        if not cleaned:
+            raise ValueError("artist name must not be empty")
+        artist = (await self.session.execute(
+            select(Artist).where(Artist.id == artist_id)
+        )).scalar_one_or_none()
+        if artist is None:
+            return None
+        artist.name = cleaned
+        await self.session.commit()
+        return artist
+
     async def autocomplete(self, prefix: str, limit: int = 20) -> list[Artist]:
         cleaned = (prefix or "").strip()
         if not cleaned:

frontend/src/components/artist/ArtistHeader.vue

@@ -1,8 +1,21 @@
 <template>
   <header class="fc-artist-header">
     <div class="fc-artist-header__left">
-      <h1 class="fc-artist-header__name">{{ name }}</h1>
-      <span v-if="stats" class="fc-artist-header__stats">{{ stats }}</span>
+      <template v-if="!editing">
+        <h1 class="fc-artist-header__name">{{ name }}</h1>
+        <v-icon
+          class="fc-artist-header__edit" size="16" icon="mdi-pencil"
+          title="Rename artist (display name only)" @click="startEdit"
+        />
+      </template>
+      <v-text-field
+        v-else
+        v-model="draft"
+        density="compact" variant="outlined" hide-details autofocus
+        class="fc-artist-header__edit-field"
+        @keydown.enter="submit" @keydown.esc="cancel" @blur="cancel"
+      />
+      <span v-if="stats && !editing" class="fc-artist-header__stats">{{ stats }}</span>
     </div>
     <v-tabs
       :model-value="modelValue"
@@ -34,7 +47,7 @@
 </template>
 
 <script setup>
-import { computed } from 'vue'
+import { computed, ref } from 'vue'
 import { formatLocalDate } from '../../utils/date.js'
 
 const props = defineProps({
@@ -45,7 +58,23 @@ const props = defineProps({
   modelValue:  { type: String, required: true },
 })
 
-defineEmits(['update:modelValue'])
+const emit = defineEmits(['update:modelValue', 'rename'])
+
+// Inline rename (display name only — #130). Mirrors TagCard's pencil-edit.
+const editing = ref(false)
+const draft = ref('')
+function startEdit () {
+  draft.value = props.name
+  editing.value = true
+}
+function cancel () {
+  editing.value = false
+}
+function submit () {
+  const next = draft.value.trim()
+  editing.value = false
+  if (next && next !== props.name) emit('rename', next)
+}
 
 const stats = computed(() => {
   const parts = []
@@ -111,6 +140,20 @@ const stats = computed(() => {
   text-overflow: ellipsis;
 }
 
+.fc-artist-header__edit {
+  flex: 0 0 auto;
+  opacity: 0;
+  cursor: pointer;
+  color: rgb(var(--v-theme-on-surface-variant));
+  transition: opacity .15s ease;
+}
+.fc-artist-header__left:hover .fc-artist-header__edit { opacity: .7; }
+.fc-artist-header__edit:hover { opacity: 1; }
+.fc-artist-header__edit-field {
+  max-width: 340px;
+  font-family: 'Fraunces', Georgia, serif;
+}
+
 .fc-artist-header__tabs {
   flex: 0 0 auto;
 }

frontend/src/stores/artist.js

@@ -73,6 +73,16 @@ export const useArtistStore = defineStore('artist', () => {
     }
   }
 
+  // Rename the DISPLAY name only (#130). The slug is immutable, so the route
+  // (slug-based) and on-disk paths are unaffected — just patch the shown name.
+  async function rename (name) {
+    if (!overview.value) return
+    const id = overview.value.id
+    const body = await api.patch(`/api/artists/${id}`, { body: { name } })
+    if (overview.value && overview.value.id === id) overview.value.name = body.name
+    return body
+  }
+
   const hasMoreImages = computed(() => !started || nextCursor.value !== null)
   const postCount = computed(() => overview.value?.post_count ?? null)
   const imageCount = computed(() => overview.value?.image_count ?? null)
@@ -81,6 +91,6 @@ export const useArtistStore = defineStore('artist', () => {
   return {
     overview, images, loading, imagesLoading, error, notFound,
     hasMoreImages, postCount, imageCount, lastAdded,
-    load, loadMoreImages,
+    load, loadMoreImages, rename,
   }
 })

frontend/src/views/ArtistView.vue

@@ -18,6 +18,7 @@
       :image-count="store.imageCount"
       :post-count="store.postCount"
       :last-added="store.lastAdded"
+      @rename="onRename"
     />
     <v-container fluid class="pt-2 pb-4">
       <!-- "N new since last visit" banner. Visible only on the initial
@@ -59,6 +60,7 @@ import { computed, ref, watch } from 'vue'
 import { useRoute } from 'vue-router'
 
 import { useArtistStore } from '../stores/artist.js'
+import { toast } from '../utils/toast.js'
 import ArtistHeader from '../components/artist/ArtistHeader.vue'
 import ArtistPostsTab from '../components/artist/ArtistPostsTab.vue'
 import ArtistGalleryTab from '../components/artist/ArtistGalleryTab.vue'
@@ -76,6 +78,17 @@ const { tab, resolve } = useTabQuery(
   () => ((store.postCount ?? 0) > 0 ? 'posts' : 'gallery'),
 )
 
+// Rename the artist's display name (#130). Slug/route unchanged, so no
+// navigation — the header just reflects the new name; also refresh the tab title.
+async function onRename (name) {
+  try {
+    await store.rename(name)
+    document.title = `${store.overview.name} — FabledCurator`
+  } catch (e) {
+    toast({ text: `Rename failed: ${e.message}`, type: 'error' })
+  }
+}
+
 // One-shot banner — reset on each new artist-slug load so it re-appears
 // when navigating between artists that each have unseen content.
 const unseenBanner = ref(false)

tests/test_api_artists_create.py

@@ -47,3 +47,28 @@ async def test_autocomplete_empty_query(client):
     resp = await client.get("/api/artists/autocomplete?q=")
     assert resp.status_code == 200
     assert await resp.get_json() == []
+
+
+@pytest.mark.asyncio
+async def test_patch_renames_display_name_only(client):
+    # #130: PATCH renames the display name; slug unchanged (paths safe).
+    created = await (await client.post("/api/artists", json={"name": "12345678"})).get_json()
+    resp = await client.patch(
+        f"/api/artists/{created['id']}", json={"name": "Kurotsuchi Machi"}
+    )
+    assert resp.status_code == 200
+    body = await resp.get_json()
+    assert body["name"] == "Kurotsuchi Machi"
+    assert body["slug"] == created["slug"]        # slug frozen
+
+
+@pytest.mark.asyncio
+async def test_patch_rename_validation(client):
+    created = await (await client.post("/api/artists", json={"name": "Nn"})).get_json()
+    assert (await client.patch(
+        f"/api/artists/{created['id']}", json={"name": "  "}
+    )).status_code == 400
+    assert (await client.patch(
+        f"/api/artists/{created['id']}", json={})).status_code == 400
+    assert (await client.patch(
+        "/api/artists/999999", json={"name": "Ghost"})).status_code == 404

tests/test_artist_service_find_or_create.py

@@ -54,3 +54,40 @@ async def test_autocomplete_ranks_exact_prefix_substring(db):
 async def test_autocomplete_empty_query_returns_empty(db):
     svc = ArtistService(db)
     assert await svc.autocomplete("") == []
+
+
+@pytest.mark.asyncio
+async def test_rename_changes_name_not_slug(db):
+    # #130: rename touches the display name ONLY — the slug (and every on-disk
+    # path keyed off it) is immutable.
+    svc = ArtistService(db)
+    artist, _ = await svc.find_or_create("12345678")
+    orig_slug = artist.slug
+    renamed = await svc.rename(artist.id, "Kurotsuchi Machi")
+    assert renamed.name == "Kurotsuchi Machi"
+    assert renamed.slug == orig_slug          # slug frozen
+    fresh = await db.get(Artist, artist.id)
+    assert fresh.name == "Kurotsuchi Machi"
+    assert fresh.slug == orig_slug
+
+
+@pytest.mark.asyncio
+async def test_rename_rejects_empty_and_missing(db):
+    svc = ArtistService(db)
+    artist, _ = await svc.find_or_create("Someone")
+    with pytest.raises(ValueError):
+        await svc.rename(artist.id, "   ")
+    assert await svc.rename(999999, "Ghost") is None
+
+
+@pytest.mark.asyncio
+async def test_two_artists_can_share_a_display_name(db):
+    # #130: name is non-unique now (two genuinely different creators can share a
+    # display name); the immutable slug keeps them distinct.
+    a = Artist(name="Same Name", slug="same-name")
+    b = Artist(name="Same Name", slug="same-name-2")
+    db.add_all([a, b])
+    await db.flush()
+    assert a.id != b.id
+    assert a.name == b.name
+    assert a.slug != b.slug