feat: right-click menus everywhere, workspace/session cost, long-term DB safety

Right-click menus: one portal shell (components/ContextMenu.tsx) for every
item with actions - sidebar/Recents/archived session rows (SessionMenu),
console tabs, pane headers, the Changes panel's files/tree/commits, the
workspace home, sessions outside a workspace (SessionRowMenu: Sessions
table, Dashboard, Activity, Workflow runs), prompt images, every Settings
list and every Claude Code/Codex config list (FileItemMenu). Buttons stay;
a delete keeps its button's confirm; the shell stops portal clicks from
reaching the card that opened it.

Status bar: Workspace $ and Session $ on the Workspace page, from
?lane= on GET /api/pricing/cost and the focused/replayed session's cost.

Database, no data dropped: synchronous=NORMAL, journal_size_limit 64 MB,
hourly PASSIVE checkpoint + PRAGMA optimize, idx_events_session_created
(replacing the redundant idx_events_session), watchdog reads
sessions.transcript_path, transcript parsed before the hook's write
transaction, GET /api/sessions/:id?events=0 for the web page (reloads only
on its own session, debounced), streamed export, transactional clear-data
and chunked cleanup, subagent import reads tool_use_ids once, runtime logs
rotated past 5 MB.

client/src/components/AlertsNotifications.tsx

@@ -8,6 +8,7 @@
  *   • Activity - the live fired-alert feed with acknowledge controls
  * Tab badges reflect live state (rule count, unacked alert count), and the feed
  * + counts refetch on alert_triggered / alert_updated WebSocket messages.
+ * A right-click on a rule opens its Enable/Disable and Delete as a menu.
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 /* =============================================================================
@@ -85,6 +86,7 @@ import { WebhookSettings } from "./WebhookSettings";
 import { ConfirmModal } from "./ConfirmModal";
 import { Checkbox } from "./Checkbox";
 import { FieldHelp } from "./FieldHelp";
+import { ContextMenu, MenuItem, MenuSeparator, useContextMenu } from "./ContextMenu";
 import { timeAgo } from "../lib/format";
 import type { AlertEvent, AlertRule, AlertRuleType, WSMessage } from "../lib/types";
 
@@ -218,6 +220,13 @@ export function AlertsNotifications() {
   const [formError, setFormError] = useState<string | null>(null);
   const [saving, setSaving] = useState(false);
   const [confirmRule, setConfirmRule] = useState<AlertRule | null>(null);
+  const ruleCtx = useContextMenu<AlertRule>();
+  // A rule-menu item: close the menu, then act on the rule it was opened on.
+  const pickRule = (fn: (rule: AlertRule) => unknown) => () => {
+    const rule = ruleCtx.menu?.item;
+    ruleCtx.close();
+    if (rule) fn(rule);
+  };
 
   // Feed
   const [alerts, setAlerts] = useState<AlertEvent[]>([]);
@@ -670,6 +679,7 @@ export function AlertsNotifications() {
               {rules.map((rule) => (
                 <li
                   key={rule.id}
+                  onContextMenu={(e) => ruleCtx.open(e, rule)}
                   className="flex flex-wrap items-center justify-between gap-3 rounded-lg border border-border bg-surface-2 px-3 py-2.5"
                 >
                   <div className="min-w-0">
@@ -713,6 +723,22 @@ export function AlertsNotifications() {
               ))}
             </ul>
           )}
+          {ruleCtx.menu && (
+            <ContextMenu
+              x={ruleCtx.menu.x}
+              y={ruleCtx.menu.y}
+              onClose={ruleCtx.close}
+              testId="alert-rule-menu"
+            >
+              <MenuItem onSelect={pickRule(onToggleRule)}>
+                {ruleCtx.menu.item.enabled ? t("rules.disable") : t("rules.enable")}
+              </MenuItem>
+              <MenuSeparator />
+              <MenuItem danger onSelect={pickRule(setConfirmRule)}>
+                {t("rules.delete")}
+              </MenuItem>
+            </ContextMenu>
+          )}
         </div>
       )}