chore: Refactor CI workflows for pipeline consolidation and manual dispatch triggers

- Updated quality-checks.yml to support manual dispatch with frontend checks.
- Modified rate-limit-integration.yml to remove workflow_run triggers and adjust conditions for execution.
- Removed pull request triggers from repo-health.yml, retaining only scheduled and manual dispatch.
- Adjusted security-pr.yml and supply-chain-pr.yml to eliminate workflow_run dependencies and refine execution conditions.
- Cleaned up supply-chain-verify.yml by removing workflow_run triggers and ensuring proper execution conditions.
- Updated waf-integration.yml to remove workflow_run triggers, allowing manual dispatch only.
- Revised current_spec.md to reflect the consolidation of CI workflows into a single pipeline, detailing objectives, research findings, and implementation plans.

.docker/compose/docker-compose.playwright-ci.yml

@@ -27,7 +27,7 @@ services:
   # Charon Application - Core E2E Testing Service
   # =============================================================================
   charon-app:
-    # CI provides CHARON_E2E_IMAGE_TAG=charon:e2e-test (locally built image)
+    # CI provides CHARON_E2E_IMAGE_TAG=charon:e2e-test (retagged from shared digest)
     # Local development uses the default fallback value
     image: ${CHARON_E2E_IMAGE_TAG:-charon:e2e-test}
     container_name: charon-playwright