fix(ui): open a chat draft when a chat scratch directory is forwarded

'New session in the current directory' callers (shortcut, menu, composer)
forward the current session's directory even when that session is a
chat. Its managed scratch directory names no project, but it counted as
an explicit project target, so a plus pressed inside a chat session
opened a project draft. Chat scratch overrides now resolve to a chat
draft.

packages/ui/src/sync/session-ui-store.test.js

@@ -592,6 +592,32 @@ describe('openNewSessionDraft project binding', () => {
     expect(useSessionUIStore.getState().newSessionDraft.target).toBe('chat');
   });
 
+  test('a chat scratch directory forwarded as override opens a chat draft', () => {
+    // "New session in the current directory" callers forward the current
+    // session's directory even when that session is a chat; its scratch
+    // directory names no project.
+    useSessionUIStore.getState().openNewSessionDraft({
+      directoryOverride: '/Users/tester/.config/openchamber/chats/ses_chat',
+    });
+    const draft = useSessionUIStore.getState().newSessionDraft;
+
+    expect(draft.target).toBe('chat');
+    expect(draft.directoryOverride).toBeNull();
+  });
+
+  test('a chat scratch override opens Chat even when the recorded target is a project', () => {
+    getDeferredSafeStorage().setItem(
+      DRAFT_TARGET_KEY,
+      JSON.stringify({ projectId: projectB.id, directory: projectB.path, target: 'project' }),
+    );
+
+    useSessionUIStore.getState().openNewSessionDraft({
+      directoryOverride: '/Users/tester/.config/openchamber/chats/ses_chat',
+    });
+
+    expect(useSessionUIStore.getState().newSessionDraft.target).toBe('chat');
+  });
+
   test('falls back to Chat when the last project target no longer exists', () => {
     getDeferredSafeStorage().setItem(
       DRAFT_TARGET_KEY,

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

@@ -1115,9 +1115,15 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
     const currentDirectory = normalizePath(useDirectoryStore.getState().currentDirectory ?? null)
     const persistedTarget = readPersistedDraftTarget()
 
-    const explicitDirectory = options?.directoryOverride !== undefined
+    // Callers that forward "the current session's directory" forward it for
+    // chat sessions too, and a chat session's scratch directory names no
+    // project. Treating it as an explicit project target would force a project
+    // draft rooted in scratch; it is a request for another chat.
+    const rawExplicitDirectory = options?.directoryOverride !== undefined
       ? normalizePath(options.directoryOverride)
       : null
+    const explicitDirectoryIsChat = rawExplicitDirectory !== null && isChatDirectoryPath(rawExplicitDirectory)
+    const explicitDirectory = explicitDirectoryIsChat ? null : rawExplicitDirectory
     const persistedProjectById = persistedTarget?.projectId
       ? projects.find((p) => p.id === persistedTarget.projectId) ?? null
       : null
@@ -1138,7 +1144,7 @@ export const useSessionUIStore = create<SessionUIState>()((set, get) => ({
 
     let target = isVSCodeRuntime() ? "project" : options?.target
     if (!target) {
-      const hasExplicitProjectTarget = options?.directoryOverride !== undefined
+      const hasExplicitProjectTarget = (options?.directoryOverride !== undefined && !explicitDirectoryIsChat)
         || (options?.selectedProjectId !== undefined && options.selectedProjectId !== CHAT_DRAFT_PROJECT_ID)
         || isVSCodeRuntime()
       target = options?.selectedProjectId === CHAT_DRAFT_PROJECT_ID