feat(gallery): tag→gallery nav from modal chips (#5) + OR/exclude tag scope (#6a)

Cluster A, milestone #97. #5: clicking an image-modal tag chip's body now
closes the modal and opens the gallery filtered for that one tag (fresh
filter); ✕/kebab stay as the explicit remove/rename controls.

#6a (backend of OR/exclude filtering): gallery_service._apply_scope gains a
structured tag model — tag_or_groups (AND-of-OR: one EXISTS(tag_id IN group)
per group) + tag_exclude (NOT EXISTS(tag_id IN exclude)) — layered additively
on the existing tag_ids AND path so cursors/facets/deep-links are untouched.
Threaded through scroll/timeline/jump_cursor/facets/similar + facets common
dict; _require_single_filter rejects post_id combined with OR/exclude. API
parses tag_or (repeatable → one OR-group each) + tag_not (csv exclude).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XCUHUGQLrBrkgyk1t49kpX

frontend/src/components/modal/TagChip.vue

@@ -3,6 +3,10 @@
     <v-chip
       size="small" closable
       :color="store.colorFor(tag.kind)" variant="tonal"
+      class="fc-tag-chip__nav"
+      role="link"
+      :title="`Browse images tagged “${tag.name}”`"
+      @click="$emit('navigate', tag)"
       @click:close="$emit('remove', tag.id)"
     >
       <v-icon start size="x-small">{{ iconFor(tag.kind) }}</v-icon>
@@ -30,7 +34,7 @@ import { useTagStore } from '../../stores/tags.js'
 import KebabMenu from '../common/KebabMenu.vue'
 
 const props = defineProps({ tag: { type: Object, required: true } })
-defineEmits(['remove', 'rename', 'set-fandom'])
+defineEmits(['remove', 'rename', 'set-fandom', 'navigate'])
 
 const store = useTagStore()
 
@@ -53,6 +57,13 @@ function iconFor (k) { return KIND_ICONS[k] || 'mdi-tag' }
 
 <style scoped>
 .fc-tag-chip { display: inline-flex; align-items: center; gap: 1px; }
+/* The chip body navigates to the filtered gallery (#5); signal it's clickable.
+   The close ✕ (remove) and the sibling kebab stay as the explicit controls. */
+.fc-tag-chip__nav { cursor: pointer; }
+.fc-tag-chip__nav:focus-visible {
+  outline: 2px solid rgb(var(--v-theme-accent));
+  outline-offset: 1px;
+}
 .fc-tag-chip__kebab { opacity: 0.7; }
 .fc-tag-chip:hover .fc-tag-chip__kebab { opacity: 1; }
 .fc-tag-chip__fandom { opacity: 0.7; font-size: 0.85em; }

frontend/src/components/modal/TagPanel.vue

@@ -6,6 +6,7 @@
         v-for="tag in modal.current?.tags || []"
         :key="tag.id" :tag="tag"
         @remove="onRemove" @rename="openRename" @set-fandom="openSetFandom"
+        @navigate="onNavigate"
       />
       <span v-if="!modal.current?.tags?.length" class="text-caption">No tags yet.</span>
     </div>
@@ -51,6 +52,7 @@
 
 <script setup>
 import { ref } from 'vue'
+import { useRouter } from 'vue-router'
 import { useModalStore } from '../../stores/modal.js'
 import { useSuggestionsStore } from '../../stores/suggestions.js'
 import TagChip from './TagChip.vue'
@@ -61,9 +63,18 @@ import FandomSetDialog from './FandomSetDialog.vue'
 
 const modal = useModalStore()
 const suggestions = useSuggestionsStore()
+const router = useRouter()
 const errorMsg = ref(null)
 const tagInputRef = ref(null)
 
+// #5: clicking a tag chip's body leaves the modal and opens the gallery
+// filtered for that single tag (a fresh filter — the obvious "show me more
+// like this tag" move). Rename/set-fandom (kebab) and remove (✕) stay put.
+async function onNavigate(tag) {
+  await modal.close()
+  router.push({ name: 'gallery', query: { tag_id: String(tag.id) } })
+}
+
 // Return focus to the tag input after a suggestion is accepted (from the
 // Suggestions panel or the autocomplete dropdown) so the operator can keep
 // typing the next tag without re-clicking the field (operator-asked 2026-06-08).