feat: add 5 PM features — custom statuses, Gantt, quick-add, automations, notifications

- Custom workflow statuses: per-project configurable status definitions
  replacing the fixed task_status enum. Each project defines its own
  workflow with drag-to-reorder, color coding, and category mapping.
- Gantt/timeline view: full project roadmap with task bars, dependency
  arrows, milestone diamonds, zoom levels (day/week/month), and drag
  to reschedule.
- Natural-language quick-add: NLP parser extracts dates, priorities,
  projects, labels, and recurrence from free text. Floating bar with
  'n' shortcut and live parsed preview.
- Automation rules: no-code trigger-action system per project. Triggers
  on status change, task creation, due date approaching. Actions set
  status/priority, add labels, create notifications.
- Notification center: in-app bell icon with unread badge, slide-out
  panel, real-time SSE updates, mark read/all read. Replaces raw
  activity feed dropdown.

Schema: adds status_definitions, automation_rules, notifications tables.
Migrations: 0007, 0008, 0009. 41 NLP parser tests pass.

apps/api/src/routes/comments.ts

@@ -14,6 +14,7 @@ import { and, asc, eq, inArray, isNull } from "drizzle-orm";
 import type { AnyPgColumn, AnyPgTable } from "drizzle-orm/pg-core";
 import { requireAuth, requireWorkspaceAccess, createErrorResponse, AuthError, isUuid } from "../middleware/auth";
 import { recordActivity } from "../middleware/activity";
+import { notifyWorkspaceOwner } from "../lib/notify";
 import { z } from "zod";
 
 export const commentRoutes = new Hono();
@@ -150,6 +151,23 @@ commentRoutes.post("/", async (c) => {
       workspaceId: domainId,
     });
 
+    // Mention notification: any @mention in the comment notifies the workspace
+    // owner (single-user MVP — there is no other recipient to resolve).
+    if (/\B@[a-zA-Z0-9_.-]+/.test(data.content)) {
+      try {
+        await notifyWorkspaceOwner({
+          workspaceId: domainId,
+          type: "mention",
+          title: "You were mentioned",
+          body: `${user.name} mentioned you in a comment on this ${data.entityType.replace(/_/g, " ")}`,
+          entityType: data.entityType,
+          entityId: data.entityId,
+        });
+      } catch (notifyError) {
+        console.error(`[comments] Failed to create mention notification for ${data.entityType}:${data.entityId}:`, notifyError);
+      }
+    }
+
     return c.json(newComment, 201);
   } catch (error) {
     if (error instanceof AuthError) {