copy: the product says "tags" now, and the schema keeps saying Label

Two words for one concept cost real comprehension: over a single exchange
the operator concluded that auto-tagging did not exist (it does, in
`derive.rs`) and that a tag-management view did not exist (it does,
`LabelsModal.vue`). The `#` is how most of these get made, so the `#` wins
the noun.

User-visible strings only, on all three surfaces plus the server's errors.
`Label`, `NoteLabel`, `via_tag`, `label_id`, the tables, `/api/labels` and
the FFI names are all untouched — renaming those touches migrations and the
wire format to buy nothing a reader can see.

Two of these were more than a find-and-replace:

  * Android's `label_from_tag` said "from #tag", sitting beside a chip that
    already renders as `#name`. Once every one of them IS a tag that hint is
    circular. What it actually tells you is that the note's BODY owns this
    one — which is why it alone has no remove cross — so it now says "from
    the text".

  * The web's empty state said "No labels yet — create one above" while
    Android's already mentioned the `#` route. The web now says it too. That
    is the exact fact the operator did not have.

The paired `aria-label`s went with their `title`s; a screen reader saying
"label" while the tooltip says "tag" is the same confusion with a smaller
audience.

Left alone deliberately: `json_error("invalid label")` and
`"label_ids must be a list"` in `notes/__init__.py` name the `?label=` query
parameter and the `label_ids` request field. Those are wire surface, not the
word a person reads.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01K3MMqUtzX1TJgA1oypvm1c

frontend/src/components/LabelsModal.vue

@@ -67,7 +67,7 @@ async function doMerge(sourceId: string, targetId: string) {
 <template>
   <BaseModal panel-class="w-full max-w-sm shadow-xl" @close="emit('close')">
     <div class="flex items-center justify-between border-b border-neutral-100 px-4 py-3 dark:border-neutral-800">
-        <h2 class="text-sm font-semibold">Manage labels</h2>
+        <h2 class="text-sm font-semibold">Manage tags</h2>
         <button type="button" class="icon-btn" aria-label="Close" @click="emit('close')"><Icon name="close" /></button>
       </div>
       <div class="flex flex-col gap-2 p-4">
@@ -76,7 +76,7 @@ async function doMerge(sourceId: string, targetId: string) {
           <input
             v-model="newName"
             type="text"
-            placeholder="Create label"
+            placeholder="Create tag"
             class="flex-1 rounded-md border border-neutral-300 bg-white px-2 py-1.5 text-sm outline-none focus-visible:ring-2 focus-visible:ring-brand dark:border-neutral-700 dark:bg-neutral-800"
           />
         </form>
@@ -87,7 +87,7 @@ async function doMerge(sourceId: string, targetId: string) {
               class="h-4 w-4 shrink-0 rounded-full border border-black/10 transition hover:scale-110 focus:outline-none focus-visible:ring-2 focus-visible:ring-brand dark:border-white/15"
               :class="labelDot(lb)"
               :title="`Color: ${NOTE_COLOR_LABELS[resolveLabelColor(lb)]}`"
-              aria-label="Change label color"
+              aria-label="Change tag color"
               @click="openColor(lb.id)"
             />
             <input
@@ -104,8 +104,8 @@ async function doMerge(sourceId: string, targetId: string) {
               v-if="canMerge"
               type="button"
               class="icon-btn"
-              title="Merge into another label"
-              aria-label="Merge into another label"
+              title="Merge into another tag"
+              aria-label="Merge into another tag"
               @click="openMerge(lb.id)"
             >
               <Icon name="merge" />
@@ -113,8 +113,8 @@ async function doMerge(sourceId: string, targetId: string) {
             <button
               type="button"
               class="icon-btn"
-              title="Delete label"
-              aria-label="Delete label"
+              title="Delete tag"
+              aria-label="Delete tag"
               @click="labels.remove(lb.id)"
             >
               <Icon name="trash" />
@@ -160,7 +160,7 @@ async function doMerge(sourceId: string, targetId: string) {
           </li>
         </ul>
         <p v-if="!labels.items.length" class="py-2 text-center text-xs text-neutral-400">
-          No labels yet — create one above.
+          No tags yet — create one above, or write a #tag in a note and it becomes one.
         </p>
       </div>
   </BaseModal>