fix(sessions): fall back when lastDirectory is a deleted worktree

New chats inherited a persisted lastDirectory even after that worktree
was removed, so the first message saved but the prompt never started.
Validate the implicit draft directory, fall back to the active project
only when OpenCode confirms the path is missing, and leave explicit
worktree targets and unknown probes unchanged.

Co-authored-by: serkraser <serkraser@gmail.com>

packages/ui/src/sync/session-ui-store.ts

@@ -603,6 +603,63 @@ const waitForWorktreeBootstrapIfConfigured = async (directory: string | null, pr
   }
 }
 
+const resolveActiveProjectDirectory = (draft: NewSessionDraftState): string | null => {
+  const projectsState = useProjectsStore.getState()
+  return normalizePath(
+    projectsState.getActiveProject()?.path
+      ?? (draft.selectedProjectId
+        ? projectsState.projects.find((project) => project.id === draft.selectedProjectId)?.path
+        : null)
+      ?? null,
+  )
+}
+
+/**
+ * Regular new-chat drafts inherit the persisted current/last directory. If that
+ * path is confirmed missing (deleted worktree), fall back to the active project.
+ * Explicit worktree targets, in-flight worktree creation, and unknown/offline
+ * probes stay unchanged so a temporary outage cannot rewrite the destination.
+ */
+const resolveCreatableDraftDirectory = async (
+  draft: NewSessionDraftState,
+  requestedDirectory: string | null | undefined,
+): Promise<{ status: "ok"; directory: string | null | undefined } | { status: "aborted" }> => {
+  const directory = requestedDirectory ?? opencodeClient.getDirectory() ?? null
+  const isRecoverableDraftDirectory =
+    draft.open
+    && draft.preserveDirectoryOverride !== true
+    && !draft.pendingWorktreeRequestId
+    && !draft.bootstrapPendingDirectory
+    && normalizePath(draft.directoryOverride) === normalizePath(directory)
+
+  if (!isRecoverableDraftDirectory || !directory) {
+    return { status: "ok", directory }
+  }
+
+  const activeProjectDirectory = resolveActiveProjectDirectory(draft)
+  if (!activeProjectDirectory || normalizePath(directory) === activeProjectDirectory) {
+    return { status: "ok", directory }
+  }
+
+  const runtimeKey = getRuntimeKey()
+  const draftDirectory = draft.directoryOverride
+  const availability = await opencodeClient.getDirectoryAvailability(directory)
+  const currentDraft = useSessionUIStore.getState().newSessionDraft
+  const draftChanged = !currentDraft.open
+    || currentDraft.preserveDirectoryOverride !== draft.preserveDirectoryOverride
+    || currentDraft.pendingWorktreeRequestId !== draft.pendingWorktreeRequestId
+    || normalizePath(currentDraft.directoryOverride) !== normalizePath(draftDirectory)
+
+  if (getRuntimeKey() !== runtimeKey || draftChanged) {
+    return { status: "aborted" }
+  }
+
+  return {
+    status: "ok",
+    directory: availability === "missing" ? activeProjectDirectory : directory,
+  }
+}
+
 export async function materializeOpenDraftSession(selection: {
   providerID: string
   modelID: string
@@ -1416,14 +1473,16 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
     const targetFolderId = draft.targetFolderId
 
     try {
-      const dir = directoryOverride ?? opencodeClient.getDirectory()
+      const resolved = await resolveCreatableDraftDirectory(draft, directoryOverride)
+      if (resolved.status === "aborted") return null
+      const dir = resolved.directory
       const session = await createSessionAction(title, dir, parentID ?? null, metadata)
       if (!session) return null
 
       get().closeNewSessionDraft()
 
       if (targetFolderId) {
-        const scopeKey = directoryOverride || get().lastLoadedDirectory || session.directory
+        const scopeKey = dir || get().lastLoadedDirectory || session.directory
         if (scopeKey) {
           useSessionFoldersStore.getState().addSessionToFolder(scopeKey, targetFolderId, session.id)
         }