# Track: Fix Test Patches for ai_client_stub Integration

## Context

After the refactor to use `ai_client_stub` as the module alias for `app_controller`, several tests fail because they use `patch('src.ai_client.X')` which doesn't properly reach the stub's module-level functions. This is a pre-existing architectural issue that needs fixing.

## Root Cause Analysis

When tests use `patch('src.ai_client.get_current_tier', return_value='Tier 3')`:

1. `patch` creates/overrides `src.ai_client` in the `src` package namespace
2. But `app_controller` does `from src import ai_client_stub as ai_client` at module load time
3. The `ai_client` local reference in `app_controller` points directly to `ai_client_stub` module
4. Patch modifies `src.ai_client` (a different object), not `src.ai_client_stub`
5. Result: Functions in `ai_client_stub` aren't patched

## Solution Applied

Changed all patches from `patch('src.ai_client.X')` to `patch('src.ai_client_stub.X')` where the stub was the actual target.

Also updated module imports in tests to use `ai_client_stub` instead of `ai_client` where appropriate.

## Tasks Completed

1. [x] Fix AIProxyClient - add `_pending_lock` threading.Lock to __init__
2. [x] Fix test_discussion_takes_gui.py - proper mocking for tab_item via imscope
3. [x] Fix test_on_tool_log_offloading - patch path to src.ai_client_stub.get_current_tier
4. [x] Fix test_redundant_calls_in_process_pending_gui_tasks - patch paths to src.ai_client_stub
5. [x] Fix test_gcli_path_updates_adapter - use ai_client_stub module reference
6. [x] Fix test_telemetry_data_updates_correctly - patch path to src.ai_client_stub.get_token_stats
7. [x] Fix test_gui_updates_on_event - patch path to src.ai_client_stub.get_token_stats
8. [x] Run batch tests to verify all fixes

## Files Modified

- src/ai_client_proxy.py - added _pending_lock
- src/ai_client_stub.py - added module-level import for GeminiCliAdapter
- tests/test_app_controller_offloading.py
- tests/test_process_pending_gui_tasks.py
- tests/test_gui_updates.py
- tests/test_discussion_takes_gui.py

## Test Results

All previously failing tests now pass:
- test_ai_client_proxy_run.py::test_initial_state_variables ✅
- test_discussion_takes_gui.py (both tests) ✅
- test_on_tool_log_offloading ✅
- test_redundant_calls_in_process_pending_gui_tasks ✅
- test_gcli_path_updates_adapter ✅
- test_telemetry_data_updates_correctly ✅
- test_gui_updates_on_event ✅

## Checkpoints

- 169fe520 - fix(ai_client_stub): add module-level import for GeminiCliAdapter
- 12f16e9a - fix(ai_client_proxy): add _pending_lock threading.Lock
- db69e3cb - fix(tests): update discussion takes GUI tests with proper mocking