feat: multi-user support, goals editing, shared food library

Multi-user:
- Madiha account with per-user nav visibility
- Dashboard greeting uses actual user display name
- Navbar and MobileTabBar accept visibleApps prop
- Madiha sees: Dashboard, Trips, Fitness, Budget, Media (no Inventory, Reader)

Goals editing:
- Goals page now has Edit Goals mode with inline number inputs
- Saves via PUT /api/fitness/goals
- Shows "No goals set" state for new users

Food library:
- Default view shows all shared foods (not just user's recent)
- Both users see the same food database
- Cleaned up duplicates: archived Eggs (kept Egg), Green Grapes (kept Grapes),
  duplicate Bellwether Yogurt, Latte Macchiato (kept Madiha's Caramel Latte)

Add to meal buttons:
- "Add to breakfast/lunch/dinner/snack" now focuses the resolve input
  and sets the meal type so AI logs to the correct meal

frontend-v2/src/routes/(app)/fitness/+page.svelte

@@ -127,7 +127,7 @@
     try {
       const url = query
         ? `/api/fitness/foods/search?q=${encodeURIComponent(query)}&limit=30`
-        : `/api/fitness/foods/recent?limit=30`;
+        : `/api/fitness/foods?limit=100`;
       const res = await fetch(url, { credentials: 'include' });
       if (res.ok) {
         const raw = await res.json();
@@ -959,7 +959,7 @@
                 {/each}
               {/if}
 
-              <button class="add-food-btn">
+              <button class="add-food-btn" onclick={() => { resolveMeal = meal; const input = document.querySelector('.resolve-input') as HTMLInputElement; if (input) { input.focus(); input.placeholder = `Add to ${meal}...`; } }}>
                 <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><line x1="12" y1="5" x2="12" y2="19"/><line x1="5" y1="12" x2="19" y2="12"/></svg>
                 Add to {meal}
               </button>