feat: add 7 new features — exec shell, SSE events, compose import, docker resources, resource limits, email notifications, auto-updates

- Container exec/shell via WebSocket + xterm.js (subtle >_ button on cards)
- Live dashboard updates via SSE (resource alerts, health changes, update notices)
- Docker Compose import with YAML parsing, preview, and dependency-ordered deploy
- Volume & network management modal with disk usage overview
- CPU/memory resource limits on deploy and live update
- Email SMTP notifications (nodemailer) alongside Discord/Telegram/ntfy
- Scheduled auto-update scheduler with maintenance windows (daily/weekly/monthly)

New deps: ws, js-yaml, nodemailer

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

status/js/container-exec.js

@@ -0,0 +1,157 @@
+// ========== CONTAINER EXEC / SHELL (WebSocket + xterm.js) ==========
+(function() {
+  injectModal('exec-modal', `<div id="exec-modal" class="weather-modal">
+    <div class="weather-modal-content" style="min-width: 700px; max-width: 900px; padding-bottom: 0;">
+      <h3 id="exec-title">Terminal</h3>
+      <div id="exec-terminal" style="height: 420px; border-radius: 6px; overflow: hidden; background: #1e1e1e;"></div>
+      <div class="weather-modal-buttons modal-footer-bar" style="margin-top: 8px; padding-bottom: 12px;">
+        <button id="exec-close">Close</button>
+      </div>
+    </div>
+  </div>`);
+
+  const modal = document.getElementById('exec-modal');
+  const termEl = document.getElementById('exec-terminal');
+  const closeBtn = document.getElementById('exec-close');
+
+  let term = null;
+  let ws = null;
+  let fitAddon = null;
+
+  function cleanup() {
+    if (ws) { try { ws.close(); } catch (_) {} ws = null; }
+    if (term) { try { term.dispose(); } catch (_) {} term = null; }
+    fitAddon = null;
+    termEl.innerHTML = '';
+  }
+
+  function openExec(containerId, containerName) {
+    cleanup();
+
+    document.getElementById('exec-title').textContent = `Terminal — ${containerName || containerId}`;
+    modal?.classList.add('show');
+
+    // Ensure xterm is available
+    if (typeof Terminal === 'undefined') {
+      termEl.innerHTML = '<div style="color: #f44; padding: 20px; font-family: monospace;">xterm.js not loaded</div>';
+      return;
+    }
+
+    term = new Terminal({
+      cursorBlink: true,
+      fontSize: 14,
+      fontFamily: "'Cascadia Code', 'Fira Code', 'Consolas', monospace",
+      theme: {
+        background: '#1e1e1e',
+        foreground: '#d4d4d4',
+        cursor: '#aeafad',
+        selectionBackground: '#264f78',
+      },
+      scrollback: 5000,
+    });
+
+    // Fit addon
+    if (typeof FitAddon !== 'undefined') {
+      fitAddon = new FitAddon.FitAddon();
+      term.loadAddon(fitAddon);
+    }
+
+    term.open(termEl);
+    if (fitAddon) {
+      // Small delay for DOM to settle
+      setTimeout(() => fitAddon.fit(), 50);
+    }
+
+    // Connect WebSocket
+    const protocol = location.protocol === 'https:' ? 'wss:' : 'ws:';
+    ws = new WebSocket(`${protocol}//${location.host}/ws/exec/${encodeURIComponent(containerId)}`);
+    ws.binaryType = 'arraybuffer';
+
+    ws.onopen = () => {
+      term.writeln('\x1b[32mConnecting...\x1b[0m');
+      // Send initial resize
+      if (fitAddon) {
+        const dims = fitAddon.proposeDimensions();
+        if (dims) {
+          ws.send(JSON.stringify({ type: 'resize', cols: dims.cols, rows: dims.rows }));
+        }
+      }
+    };
+
+    ws.onmessage = (e) => {
+      if (typeof e.data === 'string') {
+        try {
+          const msg = JSON.parse(e.data);
+          if (msg.type === 'connected') {
+            term.writeln(`\x1b[32mConnected (${msg.shell})\x1b[0m\r\n`);
+            return;
+          }
+          if (msg.type === 'error') {
+            term.writeln(`\x1b[31mError: ${msg.message}\x1b[0m`);
+            return;
+          }
+          if (msg.type === 'exit') {
+            term.writeln('\r\n\x1b[33mSession ended.\x1b[0m');
+            return;
+          }
+        } catch (_) {}
+        // Plain text
+        term.write(e.data);
+      } else {
+        // Binary data
+        term.write(new Uint8Array(e.data));
+      }
+    };
+
+    ws.onclose = () => {
+      if (term) term.writeln('\r\n\x1b[33mDisconnected.\x1b[0m');
+    };
+
+    ws.onerror = () => {
+      if (term) term.writeln('\r\n\x1b[31mConnection error.\x1b[0m');
+    };
+
+    // Terminal input → WebSocket
+    term.onData((data) => {
+      if (ws && ws.readyState === WebSocket.OPEN) {
+        ws.send(data);
+      }
+    });
+
+    // Handle resize
+    term.onResize(({ cols, rows }) => {
+      if (ws && ws.readyState === WebSocket.OPEN) {
+        ws.send(JSON.stringify({ type: 'resize', cols, rows }));
+      }
+    });
+
+    // Re-fit on window resize
+    const resizeHandler = () => { if (fitAddon) fitAddon.fit(); };
+    window.addEventListener('resize', resizeHandler);
+
+    // Store handler for cleanup
+    modal._resizeHandler = resizeHandler;
+  }
+
+  closeBtn?.addEventListener('click', () => {
+    cleanup();
+    if (modal._resizeHandler) {
+      window.removeEventListener('resize', modal._resizeHandler);
+    }
+    modal?.classList.remove('show');
+  });
+
+  // Also close on backdrop click
+  modal?.addEventListener('click', (e) => {
+    if (e.target === modal) {
+      cleanup();
+      if (modal._resizeHandler) {
+        window.removeEventListener('resize', modal._resizeHandler);
+      }
+      modal?.classList.remove('show');
+    }
+  });
+
+  // Export
+  window.openExecModal = openExec;
+})();