feat: add weblink playlists, SSH player deployment, Caddy HTTPS, build player page

- Content model: add url column + is_weblink() for web page content items
- Player model: add deployment tracking fields (status, timestamps, message)
- Content blueprint: add add_weblink and add_weblink_to_playlist routes;
  weblinks auto-deleted when removed from playlist
- Players blueprint: add SSH deploy mode in add_player; weblink-aware playlist
- API blueprint: weblink URL served directly in playlist response;
  add /api/deploy/test-ssh and /api/deploy/player endpoints
- Admin blueprint: add build-player page (clone from Gitea, write base config);
  replace nginx status card with Caddy status on HTTPS config page
- caddy_manager: rewritten to generate proper HTTPS/internal-CA Caddyfiles
  and reload Caddy via admin API (/load) for live config updates
- ssh_deploy, background_tasks, player_build: new utils for SSH deployment
- background_tasks: push Flask app context into background thread so DB
  updates after deployment complete correctly
- ssh_deploy: robust install script detection with passwordless sudo injection
  (uses SSH credentials, cleaned up after install)
- Dockerfile: add git, sshpass, openssh-client, rsync
- docker-compose: switch nginx to Caddy on ports 80/443; add port 5000 for dev
- Templates: add_player deploy mode UI, weblink form in playlist/upload pages,
  build_player admin page, Caddy status on HTTPS config page
- Migrations: add_url_to_content, add_deployment_fields_to_player
- app.py: call db.create_all() on startup for schema bootstrap
- config.py: add PLAYER_CODE_DIR and PLAYER_REPO_URL settings

app/templates/content/upload_media.html

@@ -317,6 +317,66 @@
     </form>
 </div>
 
+<!-- ── Web Link Card ─────────────────────────────────────────────────────── -->
+<div class="card" style="margin-top: 20px;">
+    <h2 style="margin-bottom: 15px; font-size: 18px; display: flex; align-items: center; gap: 0.5rem;">
+        🌐 Add Web Page Link
+    </h2>
+    <p style="color: #6c757d; font-size: 13px; margin-bottom: 16px;">
+        Add a website URL to display on the player (e.g. a dashboard, live feed, or any public web page).
+    </p>
+
+    <form id="weblink-form" method="POST" action="{{ request.script_root }}/content/add-weblink">
+        <div style="display: grid; grid-template-columns: 1fr 1fr; gap: 16px;">
+
+            <!-- URL -->
+            <div class="form-group" style="grid-column: 1 / -1;">
+                <label for="wl-url">Web Page URL <span style="color:#e53e3e;">*</span></label>
+                <input type="url" id="wl-url" name="url" class="form-control"
+                       placeholder="https://example.com" required>
+                <small style="color:#6c757d; font-size:11px;">Must start with http:// or https://</small>
+            </div>
+
+            <!-- Description -->
+            <div class="form-group">
+                <label for="wl-description">Label / Description</label>
+                <input type="text" id="wl-description" name="description" class="form-control"
+                       placeholder="e.g. Live Dashboard">
+                <small style="color:#6c757d; font-size:11px;">Optional — shown in the media library</small>
+            </div>
+
+            <!-- Duration -->
+            <div class="form-group">
+                <label for="wl-duration">Display Duration (seconds)</label>
+                <input type="number" id="wl-duration" name="duration" class="form-control"
+                       value="30" min="5" max="3600">
+                <small style="color:#6c757d; font-size:11px;">How long to show the page per loop</small>
+            </div>
+
+            <!-- Playlist -->
+            <div class="form-group" style="grid-column: 1 / -1;">
+                <label for="wl-playlist">Add to Playlist (Optional)</label>
+                <select id="wl-playlist" name="playlist_id" class="form-control">
+                    <option value="">-- Media Library Only --</option>
+                    {% for playlist in playlists %}
+                        <option value="{{ playlist.id }}">
+                            {{ playlist.name }} ({{ playlist.orientation }}) — {{ playlist.content_count }} items
+                        </option>
+                    {% endfor %}
+                </select>
+            </div>
+        </div>
+
+        <div style="display:flex; align-items:center; gap:12px; margin-top:8px;">
+            <button type="submit" class="btn-upload" id="wl-submit-btn"
+                    style="display:inline-flex; align-items:center; gap:0.5rem; padding:10px 24px;">
+                🌐 Add Web Link
+            </button>
+            <span id="wl-status" style="font-size:13px; display:none;"></span>
+        </div>
+    </form>
+</div>
+
 <script>
     const uploadZone = document.getElementById('upload-zone');
     const fileInput = document.getElementById('file-input');
@@ -509,6 +569,44 @@
         uploadBtn.disabled = true;
         uploadBtn.innerHTML = '⏳ Uploading...';
     });
+
+    // ── Web Link form — AJAX submit ────────────────────────────────────────
+    const wlForm    = document.getElementById('weblink-form');
+    const wlBtn     = document.getElementById('wl-submit-btn');
+    const wlStatus  = document.getElementById('wl-status');
+
+    wlForm.addEventListener('submit', async (e) => {
+        e.preventDefault();
+        wlBtn.disabled = true;
+        wlBtn.textContent = '⏳ Adding…';
+        wlStatus.style.display = 'none';
+
+        try {
+            const resp = await fetch(wlForm.action, {
+                method: 'POST',
+                headers: { 'X-Requested-With': 'XMLHttpRequest' },
+                body: new FormData(wlForm),
+            });
+            const data = await resp.json();
+
+            if (data.success) {
+                wlStatus.style.color = '#38a169';
+                wlStatus.textContent = '✓ ' + data.message;
+                wlForm.reset();
+                document.getElementById('wl-duration').value = 30;
+            } else {
+                wlStatus.style.color = '#e53e3e';
+                wlStatus.textContent = '✗ ' + (data.error || 'Failed to add web link.');
+            }
+        } catch (err) {
+            wlStatus.style.color = '#e53e3e';
+            wlStatus.textContent = '✗ Network error — please try again.';
+        }
+
+        wlStatus.style.display = 'inline';
+        wlBtn.disabled = false;
+        wlBtn.innerHTML = '🌐 Add Web Link';
+    });
 </script>
 
 {% endblock %}