fix(worktrees): disable selector outside git repos

Expose isGitRepo on worktree listing and show Worktree: Unavailable while disabling the dropdown when a workspace folder is not a Git repository.

packages/ui/src/stores/worktrees.ts

@@ -9,6 +9,7 @@ const log = getLogger("api")
 
 const [worktreesByInstance, setWorktreesByInstance] = createSignal<Map<string, WorktreeDescriptor[]>>(new Map())
 const [worktreeMapByInstance, setWorktreeMapByInstance] = createSignal<Map<string, WorktreeMap>>(new Map())
+const [gitRepoStatusByInstance, setGitRepoStatusByInstance] = createSignal<Map<string, boolean | null>>(new Map())
 
 const worktreeLoads = new Map<string, Promise<void>>()
 const mapLoads = new Map<string, Promise<void>>()
@@ -26,7 +27,7 @@ function normalizeMap(input?: WorktreeMap | null): WorktreeMap {
 
 async function ensureWorktreesLoaded(instanceId: string): Promise<void> {
   if (!instanceId) return
-  if (worktreesByInstance().has(instanceId)) return
+  if (worktreesByInstance().has(instanceId) && gitRepoStatusByInstance().has(instanceId)) return
   const existing = worktreeLoads.get(instanceId)
   if (existing) return existing
 
@@ -38,6 +39,12 @@ async function ensureWorktreesLoaded(instanceId: string): Promise<void> {
         next.set(instanceId, response.worktrees ?? [])
         return next
       })
+
+      setGitRepoStatusByInstance((prev) => {
+        const next = new Map(prev)
+        next.set(instanceId, typeof response.isGitRepo === "boolean" ? response.isGitRepo : null)
+        return next
+      })
     })
     .catch((error) => {
       log.warn("Failed to load worktrees", { instanceId, error })
@@ -46,6 +53,14 @@ async function ensureWorktreesLoaded(instanceId: string): Promise<void> {
         next.set(instanceId, [])
         return next
       })
+
+      // Preserve any previous value; if unknown, keep it unknown.
+      setGitRepoStatusByInstance((prev) => {
+        if (prev.has(instanceId)) return prev
+        const next = new Map(prev)
+        next.set(instanceId, null)
+        return next
+      })
     })
     .finally(() => {
       worktreeLoads.delete(instanceId)
@@ -65,12 +80,22 @@ async function reloadWorktrees(instanceId: string): Promise<void> {
         next.set(instanceId, response.worktrees ?? [])
         return next
       })
+
+      setGitRepoStatusByInstance((prev) => {
+        const next = new Map(prev)
+        next.set(instanceId, typeof response.isGitRepo === "boolean" ? response.isGitRepo : null)
+        return next
+      })
     })
     .catch((error) => {
       log.warn("Failed to reload worktrees", { instanceId, error })
     })
 }
 
+function getGitRepoStatus(instanceId: string): boolean | null {
+  return gitRepoStatusByInstance().get(instanceId) ?? null
+}
+
 async function createWorktree(instanceId: string, slug: string): Promise<{ slug: string; directory: string; branch?: string }> {
   if (!instanceId) {
     throw new Error("Missing instanceId")
@@ -242,10 +267,12 @@ function getRootClient(instanceId: string): OpencodeClient {
 export {
   worktreesByInstance,
   worktreeMapByInstance,
+  gitRepoStatusByInstance,
   ensureWorktreesLoaded,
   reloadWorktrees,
   reloadWorktreeMap,
   ensureWorktreeMapLoaded,
+  getGitRepoStatus,
   getWorktrees,
   getWorktreeMap,
   getDefaultWorktreeSlug,