Upgrade Companies page: stats, delete, status badge, dropdown menu

Server:
- companyService.stats() returns per-company agent/issue counts in one query pair
- companyService.remove() cascades deletes across all child tables in dependency order
- GET /companies/stats endpoint (board-accessible)
- DELETE /companies/:companyId endpoint (board-only)

UI:
- Companies page shows agent count, issue count, spend/budget, and created-at per card
- Company status shown as a colored badge (active/paused/archived)
- Three-dot dropdown menu with Rename and Delete Company actions
- Inline delete confirmation to prevent accidental data loss
- 'New Company' button opens onboarding wizard instead of inline form

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

server/src/routes/companies.ts

@@ -14,6 +14,11 @@ export function companyRoutes(db: Db) {
     res.json(result);
   });
 
+  router.get("/stats", async (_req, res) => {
+    const stats = await svc.stats();
+    res.json(stats);
+  });
+
   router.get("/:companyId", async (req, res) => {
     const companyId = req.params.companyId as string;
     const company = await svc.getById(companyId);
@@ -78,5 +83,16 @@ export function companyRoutes(db: Db) {
     res.json(company);
   });
 
+  router.delete("/:companyId", async (req, res) => {
+    assertBoard(req);
+    const companyId = req.params.companyId as string;
+    const company = await svc.remove(companyId);
+    if (!company) {
+      res.status(404).json({ error: "Company not found" });
+      return;
+    }
+    res.json({ ok: true });
+  });
+
   return router;
 }