feat: add Architecture tab to PRD page and inject arch into COO context

- PRD page now has a tabbed view: PRD | Architecture
  Architecture tab renders apps, packages, infrastructure, integrations,
  and risk notes as structured cards. Only shown when arch doc exists.
- Advisor route now includes the architecture summary and key fields
  in the COO's knowledge context so the orchestrator knows what's
  been planned technically

Made-with: Cursor

app/api/projects/[projectId]/advisor/route.ts

@@ -46,6 +46,7 @@ async function buildKnowledgeContext(projectId: string, email: string): Promise<
   const vision             = (d.productVision as string)   ?? (d.vision as string) ?? '';
   const giteaRepo          = (d.giteaRepo as string)       ?? '';
   const prd                = (d.prd as string)             ?? '';
+  const architecture       = d.architecture as Record<string, unknown> | null ?? null;
   const apps               = (d.apps as Array<{ name: string; domain?: string; coolifyServiceUuid?: string }>) ?? [];
   const coolifyProjectUuid = (d.coolifyProjectUuid as string) ?? '';
   const theiaUrl           = (d.theiaWorkspaceUrl as string) ?? '';
@@ -73,6 +74,15 @@ Operating principles:
   if (coolifyProjectUuid) lines.push(`Coolify project UUID: ${coolifyProjectUuid} — use coolify_list_applications to find its apps`);
   if (theiaUrl) lines.push(`Theia IDE: ${theiaUrl}`);
 
+  // Architecture document
+  if (architecture) {
+    const archApps = (architecture.apps as Array<{ name: string; type: string; description: string }> ?? [])
+      .map(a => `  - ${a.name} (${a.type}): ${a.description}`).join('\n');
+    const archInfra = (architecture.infrastructure as Array<{ name: string; reason: string }> ?? [])
+      .map(i => `  - ${i.name}: ${i.reason}`).join('\n');
+    lines.push(`\n## Technical Architecture\nSummary: ${architecture.summary ?? ''}\n\nApps:\n${archApps}\n\nInfrastructure:\n${archInfra}`);
+  }
+
   // PRD or discovery phases
   if (prd) {
     // Claude Sonnet has a 200k token context — pass the full PRD, no truncation needed