Huge refactor: Add apkeep integration with platform detection

Major changes:
- Rename google_play_cli_upd to google_play_apkeep for clarity
- Add platform detection (macOS/Linux) for apkeep binary selection
- Implement automatic binary path resolution (local binaries or system PATH)
- Add platform_utils.py helper for OS detection and binary management

Code quality improvements:
- Remove unused imports (CollectionsMapping, os in google_play.py)
- Translate all log messages to English in google_play_apkeep.py
- Update error messages to be more descriptive and actionable

Configuration updates:
- Add python_requires='>=3.9' to setup.py
- Update Python version classifiers (3.9, 3.10, 3.11, 3.12)
- Update Dockerfile to ensure apkeep_linux is executable
- Update README.md with Python version requirements

Features:
- Automatic detection of apkeep binary (apkeep_macos or apkeep_linux)
- Fallback to system apkeep if local binary not found
- Proper error messages with platform information
- Cross-platform compatibility (macOS and Linux)

Breaking changes:
- Minimum Python version is now 3.9 (was implicitly 3.9, now explicit)
- google_play_cli_upd module renamed to google_play_apkeep

Author: npinaev

.gitignore

@@ -15,6 +15,8 @@ venv/
 
 # Compiled Python bytecode
 *.py[cod]
+__pycache__/
+*.pyc
 
 # Log files
 *.log
@@ -64,4 +66,23 @@ config
 README_DOCKER.md
 mdast_cli.egg-info/
 
-*.pkl
+*.pkl
+
+# Python package metadata
+*.egg-info/
+.pytest_cache/
+.mypy_cache/
+.ruff_cache/
+
+# IDE
+.vscode/
+*.swp
+*.swo
+*~
+
+# OS
+.DS_Store
+Thumbs.db
+
+# Application sessions (may contain sensitive data)
+appstore_sessions/