fix: silent validation and graceful re-prompt on invalid directory

Changes:
- Removed validateRepositoryAccess() that was logging errors
- Now validates silently using checkWriteAccess + validateRepo directly
- When invalid, clears path and re-prompts WITHOUT logging errors

This fixes the infinite error log loop. Now when user selects an
invalid directory and clicks Run:
1. Validation happens silently
2. Path is cleared
3. Prompt appears cleanly (no error spam)

Much cleaner UX!

Author: lucasheriques

src/renderer/features/task-detail/stores/taskExecutionStore.ts

@@ -60,35 +60,6 @@ const toClarifyingQuestions = (
   }));
 };
 
-async function validateRepositoryAccess(
-  path: string,
-  addLog: (log: AgentEvent) => void,
-): Promise<boolean> {
-  // Check if directory exists by checking write access
-  const canWrite = await window.electronAPI?.checkWriteAccess(path);
-  if (!canWrite) {
-    addLog({
-      type: "error",
-      ts: Date.now(),
-      message: `Cannot access or write to folder: ${path}`,
-    });
-    return false;
-  }
-
-  // Check if it's a valid git repository with actual content
-  const isRepo = await window.electronAPI?.validateRepo(path);
-  if (!isRepo) {
-    addLog({
-      type: "error",
-      ts: Date.now(),
-      message: `Folder is not a valid git repository: ${path}`,
-    });
-    return false;
-  }
-
-  return true;
-}
-
 export interface TodoItem {
   content: string;
   status: "pending" | "in_progress" | "completed";
@@ -576,13 +547,16 @@ export const useTaskExecutionStore = create<TaskExecutionStore>()(
           }
         }
 
-        const isValid = await validateRepositoryAccess(
-          effectiveRepoPath,
-          (log) => store.addLog(taskId, log),
-        );
+        // Quick validation without logging errors (we'll handle it gracefully)
+        const canWrite =
+          await window.electronAPI?.checkWriteAccess(effectiveRepoPath);
+        const isRepo = canWrite
+          ? await window.electronAPI?.validateRepo(effectiveRepoPath)
+          : false;
 
-        if (!isValid) {
+        if (!canWrite || !isRepo) {
           // Repository path is invalid - clear it and show the prompt again
+          // Don't log errors, just gracefully re-prompt the user
           store.setRepoPath(taskId, null);
 
           // Recursively call runTask to trigger the prompt flow