fix(tags): allow creating a same-named character in a different fandom

The autocomplete suppressed the Create row whenever any existing tag matched
name+kind — but characters are unique by (name, kind, fandom), so a same-named
character in a different fandom (e.g. another "Raven") is a valid distinct tag.
allowCreate now always offers Create for the character kind; the fandom picker
disambiguates and find_or_create is idempotent if the same fandom is re-picked.
The Create row reads "Create another \"Raven\" character (different fandom)" when
a same-name character already exists.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ttrj5P7upUTueSfoJcxEqa

frontend/src/components/modal/TagAutocomplete.vue

@@ -72,7 +72,7 @@
             </v-icon>
           </template>
           <v-list-item-title>
-            Create "{{ parsedName }}" as {{ parsedKind }}
+            {{ createLabel }}
           </v-list-item-title>
         </v-list-item>
       </template>
@@ -178,14 +178,34 @@ watch(query, () => {
   }, 200)
 })
 
+// A same-name character ALREADY exists. Characters are unique by
+// (name, kind, fandom), so this is still a valid distinct tag in another fandom.
+const sameNameCharExists = computed(() =>
+  parsedKind.value === 'character' &&
+  hits.value.some(h =>
+    h.kind === 'character' && h.name.toLowerCase() === parsedName.value.toLowerCase(),
+  ),
+)
+
 const allowCreate = computed(() => {
   const q = parsedName.value
   if (!q) return false
+  // Characters disambiguate by fandom, so a same-named character in a DIFFERENT
+  // fandom is a valid new tag — always offer Create (the fandom picker resolves
+  // it; find_or_create is idempotent if you re-pick the same fandom). Other
+  // kinds are unique by (name, kind): an exact match means it already exists.
+  if (parsedKind.value === 'character') return true
   return !hits.value.some(h =>
     h.name.toLowerCase() === q.toLowerCase() && h.kind === parsedKind.value,
   )
 })
 
+const createLabel = computed(() =>
+  sameNameCharExists.value
+    ? `Create another "${parsedName.value}" character (different fandom)`
+    : `Create "${parsedName.value}" as ${parsedKind.value}`,
+)
+
 function scorePct (s) { return `${Math.round(s.score * 100)}%` }
 
 // This image's suggestions that match the typed query, minus any the server