feat: AI flow builder, visibility model, dashboard tabs, fork UI (#88)

- AI flow builder: scaffold → branch detail → assemble → review flow
- Generate All one-click branch generation with stop/cancel
- Regenerate scaffold suggestions button
- 3-action review screen: Start Flow, Open in Editor, Build Another
- Fix Publish button gated behind !isDirty
- Fix visibility column enforcement in tree access filter
- Add ?visibility filter and author_name to GET /trees
- Dashboard tabbed flows: My Flows / My Team / Public / All
- Create button in My Flows tab, window focus reload (stale data fix)
- Fork UI with optional reason modal
- Fix account_id nullability in User type and schema
- Keep is_public and visibility in sync on updates

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

frontend/src/store/aiFlowBuilderStore.ts

@@ -29,6 +29,8 @@ interface AIFlowBuilderState {
 
   // UI state
   isLoading: boolean
+  isGeneratingAll: boolean
+  stopGeneratingAll: boolean
   error: string | null
 
   // Actions
@@ -39,6 +41,8 @@ interface AIFlowBuilderState {
   selectBranches: (branches: AIBranch[]) => void
   generateBranchDetail: (branchName: string) => Promise<void>
   assemble: () => Promise<void>
+  generateAllBranchDetails: () => Promise<void>
+  cancelGenerateAll: () => void
   reset: () => void
   setPhase: (phase: AIWizardPhase) => void
   setError: (error: string | null) => void
@@ -62,6 +66,8 @@ export const useAIFlowBuilderStore = create<AIFlowBuilderState>()((set, get) =>
   assembledTree: null,
   quota: null,
   isLoading: false,
+  isGeneratingAll: false,
+  stopGeneratingAll: false,
   error: null,
 
   loadQuota: async () => {
@@ -175,6 +181,30 @@ export const useAIFlowBuilderStore = create<AIFlowBuilderState>()((set, get) =>
     }
   },
 
+  generateAllBranchDetails: async () => {
+    const { selectedBranches, generateBranchDetail } = get()
+    const undetailed = selectedBranches.filter((b) => !b.steps)
+    if (undetailed.length === 0) return
+
+    set({ isGeneratingAll: true, stopGeneratingAll: false, error: null })
+
+    for (const branch of undetailed) {
+      if (get().stopGeneratingAll) break
+      // Set currentBranchIndex so tabs show the active branch
+      const idx = get().selectedBranches.findIndex((b) => b.name === branch.name)
+      if (idx !== -1) set({ currentBranchIndex: idx })
+      await generateBranchDetail(branch.name)
+      // If generateBranchDetail set phase to 'error', stop
+      if (get().phase === 'error') break
+    }
+
+    set({ isGeneratingAll: false })
+  },
+
+  cancelGenerateAll: () => {
+    set({ stopGeneratingAll: true })
+  },
+
   reset: () => {
     set({
       phase: 'foundation',
@@ -185,6 +215,8 @@ export const useAIFlowBuilderStore = create<AIFlowBuilderState>()((set, get) =>
       currentBranchIndex: 0,
       assembledTree: null,
       isLoading: false,
+      isGeneratingAll: false,
+      stopGeneratingAll: false,
       error: null,
     })
   },