refactor: extract apply_applet_toggle, rooms_for_user & natus helpers to utils; DRY toggle views

- epic/utils.py (new): _planet_house, _compute_distinctions, rooms_for_user
- applets/utils.py: apply_applet_toggle replaces 5 copy-pasted toggle loops
- dashboard/views.py: use apply_applet_toggle; fix double free_tokens/tithe_tokens query in wallet(); promote _compute_distinctions import to module level
- gameboard/views.py: use apply_applet_toggle & rooms_for_user; fix double free_tokens query in toggle_game_applets
- billboard/views.py: use apply_applet_toggle & rooms_for_user
- SCSS: %tt-token-fields placeholder in _tooltips.scss; _gameboard & _game-kit @extend it
- epic/tests/unit/test_utils.py (new): coverage for _planet_house fallback path

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/static_src/scss/_gameboard.scss

@@ -124,10 +124,7 @@ body.page-gameboard {
 
     padding: 0.75rem 1.5rem;
 
-    .tt-title       { font-size: 1rem; }
-    .tt-description { padding: 0.125rem; font-size: 0.75rem; }
-    .tt-shoptalk    { font-size: 0.75rem; opacity: 0.75; }
-    .tt-expiry      { font-size: 1rem; color: rgba(var(--priRd), 1); }
+    @extend %tt-token-fields;
 
     .tt-equip-btns {
         position: absolute;