feat: add document bucket auto-creation, extension defaults, and chat widget on dashboard

Auto-create documents storage bucket on first upload. Default legacy general
extensions to enabled when no toggle row exists. Add ChatWidget to dashboard
root page with open-ai-chat event support and AI assistant quick action.
Add ensureInitialized to supplier invoices route for event emission.

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

lib/core/documents/__tests__/document-service.test.ts

@@ -25,6 +25,8 @@ function makeClient(storageOverrides: Record<string, unknown> = {}) {
     from: vi.fn().mockImplementation(() => makeBuilder()),
     rpc: vi.fn().mockImplementation(async () => results[resultIdx++] ?? { data: null, error: null }),
     storage: {
+      getBucket: vi.fn().mockResolvedValue({ data: { id: 'documents' }, error: null }),
+      createBucket: vi.fn().mockResolvedValue({ data: { name: 'documents' }, error: null }),
       from: vi.fn().mockReturnValue({
         upload: vi.fn().mockResolvedValue({ data: {}, error: null }),
         download: vi.fn().mockResolvedValue({
@@ -43,14 +45,16 @@ function makeClient(storageOverrides: Record<string, unknown> = {}) {
 
 vi.mock('@/lib/supabase/server', () => ({
   createClient: vi.fn(async () => makeClient()),
+  createServiceClient: vi.fn(async () => makeClient()),
 }))
 
-import { uploadDocument, createNewVersion, verifyIntegrity } from '../document-service'
+import { uploadDocument, createNewVersion, verifyIntegrity, _resetBucketVerified } from '../document-service'
 import { createClient } from '@/lib/supabase/server'
 
 beforeEach(() => {
   vi.clearAllMocks()
   eventBus.clear()
+  _resetBucketVerified()
   resultIdx = 0
   results = []
   // Reset the mock to use default makeClient

lib/core/documents/document-service.ts

@@ -1,4 +1,4 @@
-import { createClient } from '@/lib/supabase/server'
+import { createClient, createServiceClient } from '@/lib/supabase/server'
 import { eventBus } from '@/lib/events'
 import type { DocumentAttachment, CreateDocumentAttachmentInput, DocumentUploadSource } from '@/types'
 
@@ -10,6 +10,33 @@ import type { DocumentAttachment, CreateDocumentAttachmentInput, DocumentUploadS
  * for documents linked to committed entries.
  */
 
+let bucketVerified = false
+
+/** @internal Reset bucket verification flag — for testing only */
+export function _resetBucketVerified() {
+  bucketVerified = false
+}
+
+/**
+ * Ensure the 'documents' storage bucket exists, creating it if missing.
+ * Runs once per process lifetime (same pattern as ensureInitialized).
+ */
+async function ensureDocumentsBucket(): Promise<void> {
+  if (bucketVerified) return
+
+  const supabase = await createServiceClient()
+  const { data: bucket } = await supabase.storage.getBucket('documents')
+
+  if (!bucket) {
+    await supabase.storage.createBucket('documents', {
+      public: false,
+      fileSizeLimit: 52428800, // 50 MB
+    })
+  }
+
+  bucketVerified = true
+}
+
 /**
  * Compute SHA-256 hash of a file buffer
  */
@@ -31,6 +58,7 @@ export async function uploadDocument(
     journal_entry_line_id?: string
   } = {}
 ): Promise<DocumentAttachment> {
+  await ensureDocumentsBucket()
   const supabase = await createClient()
 
   // Compute SHA-256 hash
@@ -102,6 +130,7 @@ export async function createNewVersion(
   originalId: string,
   file: { name: string; buffer: ArrayBuffer; type?: string }
 ): Promise<DocumentAttachment> {
+  await ensureDocumentsBucket()
   const supabase = await createClient()
 
   // Compute SHA-256 hash