Add onboarding wizard and revamp agent creation flow

Add OnboardingWizard component for first-time company setup. Rework
NewAgentDialog into a multi-step wizard with adapter selection and
config. Add server route for agent connection string generation.
Wire onboarding into Dashboard and Layout. Update DialogContext with
onboarding state.

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

server/src/routes/agents.ts

@@ -15,6 +15,28 @@ export function agentRoutes(db: Db) {
   const svc = agentService(db);
   const heartbeat = heartbeatService(db);
 
+  // Static model lists for adapters — can be extended to query CLIs dynamically
+  const adapterModels: Record<string, { id: string; label: string }[]> = {
+    claude_local: [
+      { id: "claude-opus-4-6", label: "Claude Opus 4.6" },
+      { id: "claude-sonnet-4-5-20250929", label: "Claude Sonnet 4.5" },
+      { id: "claude-haiku-4-5-20251001", label: "Claude Haiku 4.5" },
+    ],
+    codex_local: [
+      { id: "o4-mini", label: "o4-mini" },
+      { id: "o3", label: "o3" },
+      { id: "codex-mini-latest", label: "Codex Mini" },
+    ],
+    process: [],
+    http: [],
+  };
+
+  router.get("/adapters/:type/models", (req, res) => {
+    const type = req.params.type as string;
+    const models = adapterModels[type] ?? [];
+    res.json(models);
+  });
+
   router.get("/companies/:companyId/agents", async (req, res) => {
     const companyId = req.params.companyId as string;
     assertCompanyAccess(req, companyId);