feat: improve multi-workspace chat setup

[cynfria]

Category: improvement
User Impact: Multi-folder project chats can now configure worktree behavior up front, create and attach worktrees safely, and manage queued messages more clearly from the composer.
Problem: Multi-workspace chats did not explain or reliably coordinate worktree setup, project folder policies, session promotion, and queued-message behavior. This led to hidden worktree actions, stale workspace state, and confusing composer feedback.
Solution: Add explicit per-folder new-chat policies, an immediate composer piggyback for prompted worktree setup, and coordinated workspace/session transitions with rollback, timeout, migration, and queue-order safeguards. The UI now distinguishes Git-connected folders, preserves policy through transient Git failures, and groups queued messages consistently.

File changes

scripts/design-system-audit.mjs
Removes a stale baseline exception after Project dialog buttons moved back onto supported design-system treatments.

src-tauri/crates/berdctl/api-surface.json
src-tauri/crates/berdctl/api-surface-feedback.json
src-tauri/crates/berdctl/cli-surface.json
src-tauri/crates/berdctl/cli-surface-feedback.json
Regenerates berdctl project startup-mode contracts for manual and prompted worktree policies and legacy-mode migration.

src/app/AppShell.tsx
Starts a fresh chat after project creation, preserves full workspace state during draft promotion, and initializes project chats according to the selected workspace policy.

src/app/SessionWindowApp.tsx
Uses the shared worktree-mode interpretation when restoring session-window project context.

src/features/berdctl/commands/impl/getProject.ts
Returns the expanded project workspace startup-mode contract.

src/features/berdctl/commands/impl/setProjectStartupMode.ts
Normalizes legacy modes, applies policy only to Git workspaces, and returns the actual persisted mode.

src/features/berdctl/tests/commands/commands.test.ts
Covers current and migrated startup-mode command behavior.

src/features/chat/hooks/useChatSessionController.ts
Offers pre-send workspace setup immediately, provisions named worktrees safely, and protects async UI state from stale completions.

src/features/chat/hooks/tests/useChatSessionController.test.ts
Covers initial piggyback visibility and startup system-message behavior.

src/features/chat/hooks/useMessageQueue.ts
Prevents dismissing one queued message from sending the next message as a side effect.

src/features/chat/hooks/tests/useMessageQueue.test.ts
Protects explicit queue removal and remaining-message order.

src/features/chat/lib/firstWorkspaceSend.ts
Coordinates workspace planning, session promotion, target switching, timeout, validation, rollback, migration, and deferred-message release.

src/features/chat/lib/firstWorkspaceSend.test.ts
Adds adversarial coverage for promotion waits, rollback, stale state, interrupted setup, and policy behavior.

src/features/chat/lib/sessionTargetCoordinator.ts
Makes draft-to-backend coordinator transfer collision-safe and settles superseded operations.

src/features/chat/lib/sessionTargetCoordinator.test.ts
Covers existing backend actors and in-flight draft operation cleanup.

src/features/chat/ui/ChatInput.tsx
Places the workspace piggyback behind the composer and groups/animates queued messages in one responsive container.

src/features/chat/ui/tests/ChatInput.test.tsx
Covers piggyback ordering, grouped queue geometry, editing, and action ownership.

src/features/chat/ui/ChatView.tsx
Connects immediate and deferred workspace setup states to the composer accessory.

src/features/chat/ui/WorkspaceSetupChoice.tsx
Implements the animated worktree choice, naming, progress, and inline error states with dark-mode and reduced-motion support.

src/features/chat/ui/WorkspaceSetupChoice.test.tsx
Covers setup copy, naming validation, error layout, progress, and visual contracts.

src/features/chat/ui/widgets/WorkspaceIdentity.tsx
Supports explicit Git-folder identity icons and icon-scoped explanatory tooltips.

src/features/design-system/generated/componentManifest.ts
src/features/design-system/ui/DesignSystemView.tsx
Documents the compact 32px text-button size used by composer actions.

src/features/projects/api/projects.ts
Adds current workspace policy modes and migrates legacy branch/worktree settings.

src/features/projects/api/projects.test.ts
Covers policy normalization, migration, and persistence.

src/features/projects/lib/projectChatWorkspaces.ts
Plans project-wide worktrees, formats friendly errors, and provides rollback-safe cleanup.

src/features/projects/lib/projectChatWorkspaces.test.ts
Covers multi-folder planning, validation, rollback, and plain-English failures.

src/features/projects/ui/CreateProjectDialog.tsx
Redesigns Project folders with Git-aware icons, per-folder new-chat policy controls, policy synchronization, and non-Git handling.

src/features/projects/ui/tests/CreateProjectDialog.test.tsx
Covers Git detection, policy synchronization, transient probe failures, migration, and folder management.

src/shared/i18n/locales/en/projects.json
src/shared/i18n/locales/es/projects.json
Adds localized policy labels and concise Git-folder tooltip copy.

src/shared/ui/button.tsx
Adds a shared compact 32px text-button size for composer action groups.