fix(core,cli): properly resolve nested paths and plan dirs in exit_plan_mode

- **exit_plan_mode.ts**: Fixed an issue where `path.basename` incorrectly stripped nested directories (e.g., `tracks/123/index.md` to `index.md`) by adopting `resolveAndValidatePlanPath`.
- **UI Components**: Updated `ExitPlanModeDialog.tsx` and `planCommand.ts` to use `config.getPlansDir()` instead of `config.storage.getPlansDir()`. This ensures the UI respects active extension plan directories (like Conductor) rather than falling back to the default temporary directory.
- **write-file.ts**: Updated to use `config.getPlansDir()` for consistency.

packages/cli/src/ui/commands/planCommand.ts

@@ -82,7 +82,7 @@ export const planCommand: SlashCommand = {
     try {
       const content = await processSingleFileContent(
         approvedPlanPath,
-        config.storage.getPlansDir(),
+        config.getPlansDir(),
         config.getFileSystemService(),
       );
       const fileName = path.basename(approvedPlanPath);

packages/cli/src/ui/components/ExitPlanModeDialog.tsx

@@ -84,7 +84,7 @@ function usePlanContent(planPath: string, config: Config): PlanContentState {
       try {
         const pathError = await validatePlanPath(
           planPath,
-          config.storage.getPlansDir(),
+          config.getPlansDir(),
         );
         if (ignore) return;
         if (pathError) {
@@ -101,7 +101,7 @@ function usePlanContent(planPath: string, config: Config): PlanContentState {
 
         const result = await processSingleFileContent(
           planPath,
-          config.storage.getPlansDir(),
+          config.getPlansDir(),
           config.getFileSystemService(),
         );
 

packages/core/src/tools/exit-plan-mode.ts

@@ -63,20 +63,20 @@ export class ExitPlanModeTool extends BaseDeclarativeTool<
     if (!params.plan_filename || params.plan_filename.trim() === '') {
       return 'plan_filename is required.';
     }
-try {
-  resolveAndValidatePlanPath(
-    params.plan_filename,
-    this.config.getPlansDir(),
-  );
-} catch (e) {
-  if (e instanceof Error && e.message.startsWith('Security violation')) {
-    return `Access denied: plan path (${path.join(
-      this.config.getPlansDir(),
-      params.plan_filename,
-    )}) must be within the designated plans directory (${this.config.getPlansDir()}).`;
-  }
-  return e instanceof Error ? e.message : String(e);
-}
+    try {
+      resolveAndValidatePlanPath(
+        params.plan_filename,
+        this.config.getPlansDir(),
+      );
+    } catch (e) {
+      if (e instanceof Error && e.message.startsWith('Security violation')) {
+        return `Access denied: plan path (${path.join(
+          this.config.getPlansDir(),
+          params.plan_filename,
+        )}) must be within the designated plans directory (${this.config.getPlansDir()}).`;
+      }
+      return e instanceof Error ? e.message : String(e);
+    }
 
     return null;
   }
@@ -184,8 +184,10 @@ export class ExitPlanModeInvocation extends BaseToolInvocation<
    * Note: Validation is done in validateToolParamValues, so this assumes the path is valid.
    */
   private getResolvedPlanPath(): string {
-    const safeFilename = path.basename(this.params.plan_filename);
-    return path.join(this.config.getPlansDir(), safeFilename);
+    return resolveAndValidatePlanPath(
+      this.params.plan_filename,
+      this.config.getPlansDir(),
+    );
   }
 
   async execute({ abortSignal: _signal }: ExecuteOptions): Promise<ToolResult> {

packages/core/src/tools/write-file.ts

@@ -504,7 +504,7 @@ export class WriteFileTool
       try {
         resolvedPath = resolveAndValidatePlanPath(
           filePath,
-          this.config.storage.getPlansDir(),
+          this.config.getPlansDir(),
         );
       } catch (err) {
         return err instanceof Error ? err.message : String(err);