Move Module Loading to Web Boot Stage and Keep start() Request-Only #504

Summary

Refactor the web app lifecycle so module loading and route collection building happen once during adapter boot, not on every request. Keep start() focused on per-request execution only.

Problem

WebAppAdapter::start() currently performs module loading (loadModules()) per request. In long-lived app instances (including feature tests with multiple requests), this causes repeated DI route registration behavior and lifecycle coupling between boot and request phases.

Goals

1. Enforce lifecycle separation:

• Boot phase: one-time app setup, including module/route loading.
• Request phase: resolve route, run middleware/dispatch, send response, clean request-scoped state.

2. Prevent repeated route collection registration across requests.
3. Preserve backward-compatible request behavior (including downstream expectations around response() access after send).

Scope Requirements

1. Add/restore LoadModulesStage under src/App/Stages/:

• Register/get ModuleLoader.
• Build RouteCollection via RouteBuilder from module route closures/config.
• Store collection in DI.

2. Wire LoadModulesStage into WebAppAdapter constructor boot pipeline.
3. Remove per-request module-loading call from WebAppAdapter::start().
4. Keep start() request-only flow:

• OPTIONS handling
• route resolution
• dispatch/middleware flow
• response send + request cleanup

5. Keep request cleanup after send, but do not flush response payload in cleanup (compatibility requirement).

Non-Goals

• No redesign of DI container semantics.
• No reintroduction of handle() API unless separately scoped.
• No dynamic hot-reload of modules/routes in normal runtime path.

Acceptance Criteria

1. Core unit tests pass, including tests/Unit/App/Adapters/WebAppAdapterTest.php.
2. Multiple requests against one app instance do not trigger route collection re-registration failures.
3. Downstream feature suite passes without requiring app recreation per request.
4. Request context is cleaned after send; response payload remains readable for compatibility.

Validation Plan

1. Run core:

• vendor/bin/phpunit
• composer phpstan
• composer cs:check

2. Run downstream project full feature tests against path-linked core.
3. Smoke test CLI/web startup manually.

Risks / Notes

1. Runtime changes to module config/routes during the same app instance will no longer auto-apply per request.
2. If dynamic refresh is needed later, add an explicit "reload routing/modules" mechanism as a separate ticket.

Deliverables

1. Stage implementation file.
2. Adapter pipeline update.
3. Request-flow cleanup adjustments/tests.
4. Changelog entry describing lifecycle contract.