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>

skills-engine/__tests__/run-migrations.test.ts

@@ -32,11 +32,12 @@ describe('run-migrations', () => {
     to: string,
   ): { stdout: string; exitCode: number } {
     try {
-      const stdout = execFileSync(
-        tsxBin,
-        [scriptPath, from, to, newCoreDir],
-        { cwd: tmpDir, encoding: 'utf-8', stdio: 'pipe', timeout: 30_000 },
-      );
+      const stdout = execFileSync(tsxBin, [scriptPath, from, to, newCoreDir], {
+        cwd: tmpDir,
+        encoding: 'utf-8',
+        stdio: 'pipe',
+        timeout: 30_000,
+      });
       return { stdout, exitCode: 0 };
     } catch (err: any) {
       return { stdout: err.stdout ?? '', exitCode: err.status ?? 1 };