Resolve test gateway paths with the Windows path implementation when inputs use Windows-style syntax. This preserves the existing runnable script test suite without adding Windows-only tests.
### Motivation
- Tests that resolve the test gateway config directory were failing on Windows-style paths because the code always used the POSIX `path` module, producing mismatched separators.
- Preserve Windows path semantics when `rootDir` or an explicit config path uses Windows syntax while leaving POSIX behavior unchanged.
### Description
- Add `usesWindowsPathSyntax` and `pathForInputs` helpers to detect Windows-style paths and select `path.win32` when needed.
- Use the selected `pathModule` in `resolveConfigDirectory` to call `resolve`/`join` so Windows roots or explicit Windows dirs keep correct separators.
- Change is confined to `scripts/test-gateway.mjs` and does not alter other runtime behavior.
### Testing
- Ran `node --test scripts/*.test.mjs` which initially showed one failing path test and after the fix completed with all tests passing (`14` passed, `0` failed).
- Ran `npm test` in `services/edge-agent` and `services/edge-broker`, both suites passed (`18` and `23` tests respectively).
- Ran `node scripts/sync-ai-workflow.mjs --check` and `git diff --check` which both succeeded.
- Introduced a PHP CI test script for managing test suites.
- Consolidated Redis configuration retrieval.
- Optimized test fixture queries with dynamic object type assignments.
Transitioned from obsolete gateway object classes (`edge_gateway_shell_action_jobs_o`, `edge_gateway_shell_events_o`, `edge_gateway_shell_sessions_o`, `edge_gateway_update_jobs_o`) to the new agent implementation (`edge-gateway-agent/agent.php`).
