fix(modal,tags): five UX follow-ups

1. Hide 'archive' kind from /tags default view. Archive tags only
   appear when the user explicitly requests them via ?kind=archive.
   _get_tags_with_previews gains a default_excluded_kinds tuple that
   applies when no explicit kind filter is set.

2. Hide the 'Add' submit button on desktop (>=768px). Enter in the
   tag input (and in the fandom picker when no row is highlighted)
   already submits; the button is only needed for mobile virtual
   keyboards where Enter-to-submit is unreliable.

3. Fandom picker keyboard parity: ArrowUp/Down navigate rows, Enter
   picks a highlighted row or (if no row is highlighted) submits the
   whole add-tag form. Escape clears the highlight. Mirrors the main
   tagInput's keyboard block.

4. Tag editor merge bug: the edit modal populated nameInput.value
   with data.tag.display_name — for a character with a fandom, that
   value is 'Name (Fandom)'. Saving without stripping the suffix
   routed to a rename that never collided with the canonical bare
   name, so the merge offer never fired. Now uses data.tag.name (the
   bare form). The (Fandom) display is still shown in the fandom
   input which is rendered separately.

5. Fandom picker styling: match the main tag-form input — same
   padding, border, background, focus state. Drop the separate
   'Fandom' label; the placeholder 'Fandom (optional)' now carries
   the label role.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

app/static/js/view-modal.js

@@ -879,12 +879,30 @@ document.addEventListener('DOMContentLoaded', () => {
     });
   }
 
+  let fandomPickerSelectedIdx = -1;
+
+  function highlightFandomItem(idx) {
+    if (!fandomPickerAutocomplete) return;
+    const items = fandomPickerAutocomplete.querySelectorAll('.tag-autocomplete-item');
+    items.forEach((el, i) => el.classList.toggle('selected', i === idx));
+    fandomPickerSelectedIdx = idx;
+  }
+
+  function pickFandomRow(row) {
+    if (!row || !fandomPickerInput) return;
+    fandomPickerInput.value = row.dataset.fandomName;
+    fandomPickerInput.dataset.fandomId = row.dataset.fandomId;
+    clearFandomAutocomplete();
+    fandomPickerSelectedIdx = -1;
+  }
+
   if (fandomPickerInput) {
     fandomPickerInput.addEventListener('input', () => {
       clearTimeout(fandomPickerDebounce);
       const term = fandomPickerInput.value.trim();
-      // Any typing invalidates a previously-selected fandom id.
+      // Any typing invalidates a previously-selected fandom id + highlight.
       delete fandomPickerInput.dataset.fandomId;
+      fandomPickerSelectedIdx = -1;
       if (!term) {
         clearFandomAutocomplete();
         return;
@@ -896,6 +914,33 @@ document.addEventListener('DOMContentLoaded', () => {
           .catch(() => clearFandomAutocomplete());
       }, 150);
     });
+
+    // Keyboard parity with the main tagInput: ArrowDown/Up to navigate rows,
+    // Enter to pick a highlighted row (or submit the whole form when no row
+    // is highlighted), Escape to clear the highlight.
+    fandomPickerInput.addEventListener('keydown', (e) => {
+      const rows = fandomPickerAutocomplete
+        ? fandomPickerAutocomplete.querySelectorAll('.tag-autocomplete-item')
+        : [];
+      const count = rows.length;
+      if (e.key === 'ArrowDown' && count > 0) {
+        e.preventDefault();
+        highlightFandomItem(Math.min(fandomPickerSelectedIdx + 1, count - 1));
+      } else if (e.key === 'ArrowUp' && count > 0) {
+        e.preventDefault();
+        highlightFandomItem(Math.max(fandomPickerSelectedIdx - 1, 0));
+      } else if (e.key === 'Enter') {
+        if (fandomPickerSelectedIdx >= 0 && rows[fandomPickerSelectedIdx]) {
+          e.preventDefault();
+          pickFandomRow(rows[fandomPickerSelectedIdx]);
+        } else {
+          e.preventDefault();
+          submitTag();
+        }
+      } else if (e.key === 'Escape') {
+        highlightFandomItem(-1);
+      }
+    });
   }
 
   if (fandomPickerAutocomplete) {
@@ -903,11 +948,7 @@ document.addEventListener('DOMContentLoaded', () => {
       const row = e.target.closest('[data-fandom-id]');
       if (!row) return;
       e.preventDefault();  // keep focus on the input
-      if (fandomPickerInput) {
-        fandomPickerInput.value = row.dataset.fandomName;
-        fandomPickerInput.dataset.fandomId = row.dataset.fandomId;
-      }
-      clearFandomAutocomplete();
+      pickFandomRow(row);
     });
   }