Convert to TypeScript (#58)

* init

* Update dep version

* Address review comments from CodeRabbit and Copilot

- Use os.tmpdir() fallback instead of empty string for RUNNER_TEMP
- Add .trim().filter(Boolean) for labels/assignees/reviewers in createPullRequest
- Remove unused declaration/declarationMap from tsconfig (tsc runs with --noEmit)
- Add error handling to esbuild config

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

---------

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

Author: hawkeyexl

.gitignore

@@ -128,5 +128,8 @@ out
 .yarn/install-state.gz
 .pnp.*
 
+# Intermediate TypeScript build output
+build/
+
 # Doc Detective
 testResults-*.json