Add shareable search links and watched movie indicators

Share: "Copy Link" button generates a URL with ?s={history_id} that
loads the saved search results without auth. Recipients see the same
movie picks.

Watched: When viewing history results or shared searches, cards for
movies the logged-in user has since watched are dimmed with a green
"Watched" badge. Uses a new POST /api/library/watch-check endpoint.

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

app/static/app.js

@@ -217,6 +217,7 @@ function renderResults(data, append = false) {
     data.recommendations.forEach(movie => {
         const card = document.createElement('div');
         card.className = 'movie-card bg-dark-200 rounded-xl overflow-hidden border border-gray-800';
+        card.dataset.jellyfinId = movie.jellyfin_id;
         card.innerHTML = `
             <div class="aspect-[2/3] bg-dark-300 relative">
                 <img src="${movie.poster_url}" alt="${movie.title}"
@@ -315,11 +316,13 @@ async function loadHistory() {
     } catch { /* ignore */ }
 }
 
-function showHistoryResults(entry) {
+async function showHistoryResults(entry) {
     document.getElementById('mood-input').value = entry.mood;
     const data = { recommendations: entry.results, meta: entry.meta };
     renderResults(data);
     window.scrollTo({ top: 0, behavior: 'smooth' });
+    // Check watch state and dim watched movies
+    await markWatchedCards(entry.results.map(r => r.jellyfin_id));
 }
 
 function toggleHistoryVisibility(show) {
@@ -334,6 +337,51 @@ function toggleHistoryVisibility(show) {
     }
 }
 
+// --- Watch Check ---
+
+async function markWatchedCards(jellyfinIds) {
+    if (!currentUser || !jellyfinIds.length) return;
+    try {
+        const res = await fetch(`${API}/api/library/watch-check`, {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({ jellyfin_ids: jellyfinIds })
+        });
+        if (!res.ok) return;
+        const { watched } = await res.json();
+        if (!watched.length) return;
+        const watchedSet = new Set(watched);
+        document.querySelectorAll('.movie-card').forEach(card => {
+            if (watchedSet.has(card.dataset.jellyfinId)) {
+                card.classList.add('watched');
+            }
+        });
+    } catch { /* ignore */ }
+}
+
+// --- Shared Search ---
+
+async function loadSharedSearch() {
+    const params = new URLSearchParams(window.location.search);
+    const sharedId = params.get('s');
+    if (!sharedId) return false;
+    try {
+        const res = await fetch(`${API}/api/history/shared/${sharedId}`);
+        if (!res.ok) return false;
+        const entry = await res.json();
+        document.getElementById('mood-input').value = entry.mood;
+        const data = { recommendations: entry.results, meta: entry.meta };
+        renderResults(data);
+        // If logged in, check watch state
+        if (currentUser) {
+            await markWatchedCards(entry.results.map(r => r.jellyfin_id));
+        }
+        return true;
+    } catch {
+        return false;
+    }
+}
+
 // --- Library Stats ---
 
 async function loadStats() {
@@ -418,6 +466,20 @@ document.getElementById('reroll-btn').addEventListener('click', () => {
     findMovies(shownMovieIds);
 });
 
+// Share / Copy Link
+document.getElementById('share-btn').addEventListener('click', () => {
+    if (!currentHistoryId) return;
+    const url = `${window.location.origin}${window.location.pathname}?s=${currentHistoryId}`;
+    navigator.clipboard.writeText(url).then(() => {
+        const btn = document.getElementById('share-btn');
+        btn.textContent = 'Copied!';
+        setTimeout(() => { btn.textContent = 'Copy Link'; }, 2000);
+    }).catch(() => {
+        // Fallback for insecure contexts
+        prompt('Copy this link:', `${window.location.origin}${window.location.pathname}?s=${currentHistoryId}`);
+    });
+});
+
 // Reset
 document.getElementById('reset-btn').addEventListener('click', () => {
     // Clear mood input and state
@@ -445,3 +507,4 @@ document.getElementById('reset-btn').addEventListener('click', () => {
 
 // --- Init ---
 checkAuth();
+loadSharedSearch();