PHPStan and PHPUnit infrastructure

[dieselxxx]

Affected Version

v0.0.0

Chore Type

Build / CI Configuration

Pre-check

• I confirm this change does NOT affect application behavior

Description

This chore introduces PHPStan static analysis and PHPUnit testing framework into the FireHub Core repository.

The goal is to establish a quality baseline for:

• static analysis enforcement (type safety, architecture rules)
• automated testing infrastructure for Core components

Reason

To improve code quality, enforce architectural consistency, and introduce automated validation of Core primitives.

This ensures:

• early detection of type and design issues via PHPStan
• regression safety via PHPUnit
• foundation for CI enforcement in future pipeline stages

Changes

• Added PHPStan configuration (baseline + ruleset)
• Added PHPUnit configuration and bootstrap setup
• Introduced initial test directory structure
• Configured Composer scripts for analysis and testing
• Prepared CI-ready entry points (if applicable)

Impact

No functional changes to Core runtime or behavior.

Indirect effects:

• Increased development strictness via static analysis
• Improved feedback loop for type safety and architecture violations
• Slight increase in CI/build execution time due to analysis and tests

Additional Context

This is a foundational step toward establishing FireHub as a strictly typed, architecture-enforced framework.

Future extensions:

• CI enforcement with fail-on-PHPStan-level
• architecture rule validation (Core vs Runtime separation)
• test coverage expansion for ValueObject system