I need to develop a comprehensive test strategy and test cases for a [SOFTWARE_TYPE: e.g., web application, mobile app, API, etc.] that [SOFTWARE_PURPOSE]. Please help me create a thorough testing approach to ensure quality and reliability. Testing context: Key functionality: [KEY_FUNCTIONALITY] User types: [USER_TYPES] Critical use cases: [CRITICAL_FLOWS] Technical stack: [TECH_STACK if known] Known risk areas: [RISK_AREAS] Testing constraints: [CONSTRAINTS] Quality requirements: [QUALITY_REQUIREMENTS] Please create a complete testing strategy and test case framework including: Testing strategy overview: Testing approach and methodology Test level definitions Test type selection and rationale Environment requirements Entry and exit criteria Testing tools recommendations Risk-based testing prioritization Functional test case development: Key functional flows test cases Feature-specific test scenarios User journey-based test paths Input validation test coverage Configuration and compatibility testing Database and data integrity testing Integration point test scenarios Edge case and negative testing: Boundary value test cases Invalid input scenarios Error handling and recovery testing Unexpected user flow testing Resource limitation scenarios Concurrency and timing test cases Failure mode testing Non-functional test approach: Performance test scenarios Security testing approach Usability testing methodology Accessibility test requirements Reliability and stability testing Compatibility test matrix Regulatory compliance verification Test automation recommendations: Automation scope and prioritization Automation framework recommendations Test selection for automation Test data management approach Continuous integration strategy Automation maintenance considerations Manual vs. automated testing balance Test management and execution: Test organization and structure Traceability to requirements Defect management process Test result reporting structure Testing metrics and KPIs Test cycle planning Regression testing strategy Please provide this as a comprehensive testing strategy with detailed test case examples for key functionality, structured in a way that can be easily implemented by QA engineers.