refactor: CI optimization, logging improvements, and codebase formatting (#456)

* fix(db): remove unique constraint on folder to support multi-channel agents

* ci: implement automated skill drift detection and self-healing PRs

* fix: align registration logic with Gavriel's feedback and fix build/test issues from Daniel Mi

* style: conform to prettier standards for CI validation

* test: fix branch naming inconsistency in CI (master vs main)

* fix(ci): robust module resolution by removing file extensions in scripts

* refactor(ci): simplify skill validation by removing redundant combination tests

* style: conform skills-engine to prettier, unify logging in index.ts and cleanup unused imports

* refactor: extract multi-channel DB changes to separate branch

Move channel column, folder suffix logic, and related migrations
to feat/multi-channel-db-v2 for independent review. This PR now
contains only CI/CD optimizations, Prettier formatting, and
logging improvements.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

vitest.skills.config.ts

@@ -1,7 +0,0 @@
-import { defineConfig } from 'vitest/config';
-
-export default defineConfig({
-  test: {
-    include: ['.claude/skills/**/tests/*.test.ts'],
-  },
-});