feat(ourmoji): moon icon in mobile footer nav

Adds the Ourmoji branch to the mobile bottom-nav icon switch, using the
heroicons outline moon glyph — matches the existing footer style
(monochrome, stroke="currentColor") and reflects the module's
moon-phase context on the daily card.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: InfantLab

app/layouts/default.vue

@@ -337,6 +337,22 @@ onUnmounted(() => {
               d="M9 19v-6a2 2 0 00-2-2H5a2 2 0 00-2 2v6a2 2 0 002 2h2a2 2 0 002-2zm0 0V9a2 2 0 012-2h2a2 2 0 012 2v10m-6 0a2 2 0 002 2h2a2 2 0 002-2m0 0V5a2 2 0 012-2h2a2 2 0 012 2v14a2 2 0 01-2 2h-2a2 2 0 01-2-2z"
             />
           </svg>
+          <svg
+            v-else-if="item.name === 'Ourmoji'"
+            xmlns="http://www.w3.org/2000/svg"
+            class="h-5 w-5"
+            fill="none"
+            viewBox="0 0 24 24"
+            stroke="currentColor"
+            aria-hidden="true"
+          >
+            <path
+              stroke-linecap="round"
+              stroke-linejoin="round"
+              stroke-width="2"
+              d="M21.752 15.002A9.718 9.718 0 0118 15.75c-5.385 0-9.75-4.365-9.75-9.75 0-1.33.266-2.597.748-3.752A9.753 9.753 0 003 11.25C3 16.635 7.365 21 12.75 21a9.753 9.753 0 009.002-5.998z"
+            />
+          </svg>
           <span class="text-[10px] font-medium truncate">{{ item.name }}</span>
         </NuxtLink>
       </div>