fix(task-input): respect folderId when pre-selecting directory

[oliverb123]

Summary

• Clicking the + beside a project in the task sidebar passes that project's folderId to the new-task view, but the directory was still being pre-filled with the most-recently-accessed repo.
• Two effects in TaskInput raced to initialize selectedDirectory: a fallback to mostRecentRepo.path and a lookup driven by view.folderId. When folders hadn't loaded yet on first render, the fallback fired first and the folderId lookup never overrode it.
• Skip the fallback when view.folderId is set so the folder lookup is the sole source of truth in that case. Behavior is unchanged when no folder context is provided.

Test plan

• Start a task in Project A so it becomes the most-recently-accessed repo.
• Click the + beside Project B in the sidebar — the new-task UI should pre-select Project B's directory, not Project A's.
• Reverse the roles and repeat to confirm.
• Open the new-task UI from a global entry point (no folder context) — it should still pre-select the most-recent repo.

[greptile-apps]

_{Reviews (1): Last reviewed commit: "fix(task-input): respect folderId when p..." | Re-trigger Greptile}