feat: complete working-copies workspace-first cleanup

- Remove clone_mode/branch/new_branch from frontend create session flow.
- Add workspace picker to CreateSessionForm; auto-create default workspace when repo selected.
- Fix tool-starter.tsx and use-start-tool.ts createInstance signatures after API change.
- Remove clone mode badge from SessionCard.
- Delete stale backend unit tests referencing removed clone_mode schema fields.
- Update OpenSpec working-copies tasks and mark change completed.
- Regenerate project maps.

Quality gates: npm run typecheck, npm run lint, npm test -- --run (82 passed),
python3 -m py_compile on changed backend files.

apps/web/src/hooks/.pi-map.index.md

@@ -2,7 +2,7 @@
 dir: apps/web/src/hooks
 
 ## role
-Provides a comprehensive collection of custom React hooks that encapsulate reusable stateful logic, side effects, and API interactions for the web application's UI, data management, and domain-specific operations.
+Provides reusable React custom hooks that encapsulate UI state management, side effects, API integrations, and domain-specific logic for the web application frontend.
 ## parent
 index: apps/web/src/.pi-map.index.md
 map: apps/web/src/.pi-map.md

apps/web/src/hooks/.pi-map.md

@@ -4,7 +4,7 @@ dir: apps/web/src/hooks
 index: apps/web/src/hooks/.pi-map.index.md
 
 ## role
-Provides a comprehensive collection of custom React hooks that encapsulate reusable stateful logic, side effects, and API interactions for the web application's UI, data management, and domain-specific operations.
+Provides reusable React custom hooks that encapsulate UI state management, side effects, API integrations, and domain-specific logic for the web application frontend.
 ## files
 - use-async-data.ts | A custom React hook that manages asynchronous data fetching with loading, error, and ready states, plus a manual reload capability. | exp: func:useAsyncData(fetcher: () => Promise<T>, deps: React.DependencyList) → UseAsyncDataResult<T>, call:useState, call:useCallback, call:setStatus, call:setError, call:fetcher, call:setData, call:load, call:useEffect | dep: react
 - use-auto-hide.ts | A React custom hook that automatically hides an element after a specified timeout and provides manual controls for showing, hiding, and toggling visibility. | exp: func:useAutoHide(options: AutoHideOptions), call:useState, call:useRef, call:Date.now, call:useCallback, call:setIsVisible, call:clearTimeout, call:setTimeout, call:hide, call:show, call:useEffect | dep: react
@@ -20,7 +20,7 @@ Provides a comprehensive collection of custom React hooks that encapsulate reusa
 - use-repo-workspace.ts | A React custom hook that manages workspace state for a repository-based project, including loading project data, repositories, branches, git status, and tool types while synchronizing selection state with URL search parameters. | exp: Project, useRepoWorkspace | dep: react, react-router-dom, ../api/client, ../api/git-repositories, ../api/tool-types
 - use-special-keys.ts | Maps special keys and modifier+character combinations to ANSI escape sequences for terminal input simulation. | exp: SpecialKey, ModifierKey, func:getSequenceWithModifier(key: SpecialKey, activeModifier: ModifierKey | null) → { sequence: string; clearModifier: boolean } | null, call:char.toLowerCase, func:applyModifierToChar(char: string, modifier: ModifierKey) → string | null, call:char.toLowerCase
 - use-ssh-keys.ts | A React custom hook that manages SSH key operations including listing, generating, deleting, signing payloads, and verifying signatures. | exp: useSSHKeys | dep: react, ../api/ssh-keys, ./use-async-data
-- use-start-tool.ts | React hook that manages the state and API calls for creating and starting a tool instance on a workspace | exp: UseStartToolResult, func:useStartTool() → UseStartToolResult, call:useState, call:useCallback, call:setStarting, call:setError, call:createInstance, call:startInstance | dep: react, ../api/sessions, ../types/workspace
+- use-start-tool.ts | React hook for managing the state and API calls to create and start a tool instance on a workspace. | exp: UseStartToolResult, func:useStartTool() → UseStartToolResult, call:useState, call:useCallback, call:setStarting, call:setError, call:createInstance, call:startInstance | dep: react, ../api/sessions, ../types/workspace
 - use-terminal-page.ts | Manages terminal page state including sessions, keyboard shortcuts, fullscreen mode, mobile viewport handling, and terminal lifecycle operations. | exp: useTerminalPage | dep: react, react-router-dom, ../components/features/terminal/terminal, ../components/features/terminal/terminal-session-tabs, ./use-mobile-viewport, ./use-auto-hide, ./use-virtual-keyboard, ./use-terminal-sessions, ../api/terminal, ./use-special-keys, use-mobile-viewport, use-auto-hide, use-virtual-keyboard, use-terminal-sessions, terminal, terminal-session-tabs, api/terminal, api/sessions, use-special-keys
 - use-terminal-sessions.ts | React custom hook that manages terminal session state (CRUD operations, active session tracking) for a given instance | exp: UseTerminalSessionsResult, func:useTerminalSessions(instanceId: string) → UseTerminalSessionsResult, call:useState, call:useCallback, call:setLoading, call:setError, call:listTerminalSessions, call:setSessions, call:setActiveSessionId, call:createTerminalSession, call:closeTerminalSession, call:prev.filter, call:renameTerminalSession, call:prev.map, call:resetTerminalSession, call:loadSessions, call:useEffect | dep: react, ../api/terminal
 - use-theme.ts | React hook that fetches user theme preference on mount and applies it to the document root element via data-theme attribute | exp: func:useTheme(), call:useEffect, call:getUserConfig, call:document.documentElement.removeAttribute, call:document.documentElement.setAttribute | dep: react, ../api/settings
@@ -32,7 +32,7 @@ Provides a comprehensive collection of custom React hooks that encapsulate reusa
 - use-workspace-instances.ts | Custom React hook for managing workspace instances with CRUD operations, loading states, and error handling. | exp: UseWorkspaceInstancesResult, func:useWorkspaceInstances(workspaceId: string) → UseWorkspaceInstancesResult, call:useState, call:useCallback, call:setLoading, call:setError, call:listWorkspaceInstances, call:setInstances, call:createWorkspaceInstance, call:refresh, call:useEffect | dep: react, ../api/workspace-instances, ../api/sessions
 - use-workspaces.ts | Custom React hook that fetches and manages workspace data with loading and error states. | exp: UseWorkspacesResult, func:useWorkspaces(projectId: string, repoId: string) → UseWorkspacesResult, call:useState, call:useCallback, call:setLoading, call:setError, call:listWorkspaces, call:listAllWorkspaces, call:setWorkspaces, call:useEffect, call:refresh | dep: react, ../api/workspaces, ../types/workspace
 ## arch
-Follows the React Hooks pattern with custom hooks as the primary abstraction—each hook typically combines useState/useEffect/useCallback to manage local state, API calls, and side effects; many hooks integrate with TanStack Query/SWR-like patterns for server state (loading/error/reload), use context providers (e.g., NotificationProvider), and synchronize with URL search params; complex hooks compose simpler ones (e.g., use-terminal-page composes use-mobile-viewport, use-auto-hide) and use reducer-like state management for multi-faceted domain operations (CRUD, drag-and-drop, form handling).
+Layered utility hooks following React composition patterns, with separation between generic UI behavior hooks (async data, auto-hide, viewport, theme), infrastructure hooks (SSE, terminal, keyboard), and domain-specific data/operation hooks (workspace, git, SSH, projects, instances) that wrap API calls with loading/error states and optimistic updates.
 ## tags
 call:set, call:use, workspace, react, state, terminal, api, git
 ## symbols

apps/web/src/hooks/use-start-tool.ts

@@ -35,12 +35,9 @@ export function useStartTool(): UseStartToolResult {
 					workspace.repo_id,
 					toolTypeId,
 					displayName || workspace.name,
-					undefined,
-					undefined,
-					undefined,
+					workspace.id,
 					configProfileId,
 					[],
-					workspace.id,
 				);
 				await startInstance(
 					workspace.project_id,