…-aware logging (#4488)

## Summary

Comprehensive enhancement of Config class and command base logging with
scenario-aware context, building on the foundation from merged PRs #4483
and #4484.

## User-Facing Changes

**Enhanced logging context across all Config and command operations:**

### Before: Generic logging without context
```
DEBUG    Validating schema molecule.yml
WARNING  Driver 'default' is currently in use but config defines 'podman'
INFO     Performing prerun with role_name_check=0...
```

### After: Complete scenario and step context
```
DEBUG    smoke ➜ validate: Validating schema /path/to/molecule.yml
WARNING  smoke ➜ config: Driver 'default' is currently in use but config defines 'podman'  
INFO     smoke ➜ prerun: Performing prerun with role_name_check=0...
INFO     smoke ➜ discovery: scenario test matrix: syntax
```

## Technical Implementation

**🏗️ Config Class Enhancements:**
- Add reusable `@property _log` method to Config class for dynamic
scenario context
- Convert all Config logging calls to use scenario-aware loggers
- Enhanced validation logging with hardcoded scenario context during
bootstrap
- Improved galaxy file and driver validation warnings with full context

**🧹 Command Base Logger Consolidation:**
- Replace 5 scattered `get_scenario_logger()` calls with single global
`_log()` function
- Unified logging pattern: `_log(scenario_name, step, message,
level='info')`
- Pre-formatted messages eliminate complex placeholder handling
- Cleaner, more maintainable logger creation across all command
operations

**✅ Enhanced Test Coverage:**
- Updated `test_validate` to use `caplog` instead of mock patching
- Validates scenario logger extras: `molecule_scenario` and
`molecule_step`
- Robust verification of message content and context attributes

## Changes Included

**Config Class (4 commits):**
1. `feat: add step context to command base logger calls`
2. `feat: add scenario context to config file modification warning`  
3. `refactor: add reusable _log property to Config class`
4. `refactor: convert all Config logging to scenario-aware logging`

**Command Base Improvements (2 commits):**
5. `refactor: replace scattered logger initializations with global _log
function`
6. `fix: update test_validate to use caplog and check scenario logger
extras`

**Dependencies (Included):**
- Builds on: All cleanup commits from PR #4487 (unused logger removal)

## Dependencies

- **Depends on**: PR #4487 (unused logger cleanup)
- **Builds on**: PR #4484 (merged - dynamic properties for
dependency/provisioner/verifier)
- **Foundation**: PR #4483 (merged - enhanced logging adapter with
dual-output)

## Testing

- ✅ **Comprehensive**: All config tests passing (45/45)
- ✅ **Enhanced coverage**: Validates scenario logger extras in test
suite
- ✅ **Functional verification**: `molecule syntax` confirms enhanced
logging works
- ✅ **Backwards compatible**: No breaking changes to existing
functionality

## Impact

- **Complete Config context**: All Config operations now include
scenario and step information
- **Unified command logging**: Consistent pattern across all command
base operations
- **Better maintainability**: Single global `_log` function replaces
scattered initializations
- **Enhanced debugging**: Full context for configuration validation and
driver operations

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>