feat: add standardized testing scripts and documentation

Add comprehensive suite of testing scripts for different workflows:
- test.sh: Interactive menu for all testing operations
- quick_test.sh: Fast unit test feedback (~10-30s)
- run_tests.sh: Main test runner with full configuration options
- coverage_report.sh: Coverage analysis with HTML/JSON/terminal reports
- ci_test.sh: CI/CD optimized testing with JUnit/coverage XML output

Features:
- Colored terminal output with clear error messages
- Consistent option flags across all scripts
- Support for test markers (unit, integration, e2e, slow, etc.)
- Parallel execution support
- Coverage thresholds (default: 85%)
- Virtual environment and dependency checks

Documentation:
- Update CLAUDE.md with testing section and examples
- Expand docs/developer/testing.md with comprehensive guide
- Add scripts/README.md with quick reference

All scripts are tested and executable. This standardizes the testing
process for local development, CI/CD, and pull request workflows.

tests/unit/test_simulation_worker.py

@@ -50,7 +50,7 @@ class TestSimulationWorkerExecution:
         worker = SimulationWorker(job_id=job_id, db_path=clean_db)
 
         # Mock _prepare_data to return both dates
-        worker._prepare_data = Mock(return_value=(["2025-01-16", "2025-01-17"], []))
+        worker._prepare_data = Mock(return_value=(["2025-01-16", "2025-01-17"], [], {}))
 
         # Mock ModelDayExecutor
         with patch("api.simulation_worker.ModelDayExecutor") as mock_executor_class:
@@ -82,7 +82,7 @@ class TestSimulationWorkerExecution:
         worker = SimulationWorker(job_id=job_id, db_path=clean_db)
 
         # Mock _prepare_data to return both dates
-        worker._prepare_data = Mock(return_value=(["2025-01-16", "2025-01-17"], []))
+        worker._prepare_data = Mock(return_value=(["2025-01-16", "2025-01-17"], [], {}))
 
         execution_order = []
 
@@ -127,7 +127,7 @@ class TestSimulationWorkerExecution:
         worker = SimulationWorker(job_id=job_id, db_path=clean_db)
 
         # Mock _prepare_data to return the date
-        worker._prepare_data = Mock(return_value=(["2025-01-16"], []))
+        worker._prepare_data = Mock(return_value=(["2025-01-16"], [], {}))
 
         def create_mock_executor(job_id, date, model_sig, config_path, db_path):
             """Create mock executor that simulates job detail status updates."""
@@ -168,7 +168,7 @@ class TestSimulationWorkerExecution:
         worker = SimulationWorker(job_id=job_id, db_path=clean_db)
 
         # Mock _prepare_data to return the date
-        worker._prepare_data = Mock(return_value=(["2025-01-16"], []))
+        worker._prepare_data = Mock(return_value=(["2025-01-16"], [], {}))
 
         call_count = 0
 
@@ -223,7 +223,7 @@ class TestSimulationWorkerErrorHandling:
         worker = SimulationWorker(job_id=job_id, db_path=clean_db)
 
         # Mock _prepare_data to return the date
-        worker._prepare_data = Mock(return_value=(["2025-01-16"], []))
+        worker._prepare_data = Mock(return_value=(["2025-01-16"], [], {}))
 
         execution_count = 0
 
@@ -298,7 +298,7 @@ class TestSimulationWorkerConcurrency:
         worker = SimulationWorker(job_id=job_id, db_path=clean_db)
 
         # Mock _prepare_data to return the date
-        worker._prepare_data = Mock(return_value=(["2025-01-16"], []))
+        worker._prepare_data = Mock(return_value=(["2025-01-16"], [], {}))
 
         with patch("api.simulation_worker.ModelDayExecutor") as mock_executor_class:
             mock_executor = Mock()
@@ -521,7 +521,7 @@ class TestSimulationWorkerHelperMethods:
         worker.job_manager.get_completed_model_dates = Mock(return_value={})
 
         # Execute
-        available_dates, warnings = worker._prepare_data(
+        available_dates, warnings, completion_skips = worker._prepare_data(
             requested_dates=["2025-10-01"],
             models=["gpt-5"],
             config_path="config.json"
@@ -570,7 +570,7 @@ class TestSimulationWorkerHelperMethods:
         worker.job_manager.get_completed_model_dates = Mock(return_value={})
 
         # Execute
-        available_dates, warnings = worker._prepare_data(
+        available_dates, warnings, completion_skips = worker._prepare_data(
             requested_dates=["2025-10-01"],
             models=["gpt-5"],
             config_path="config.json"