refactor(rules): restructure into common + language-specific directories

* refactor(rules): restructure rules into common + language-specific directories

- Split 8 flat rule files into common/, typescript/, python/, golang/
- common/ contains language-agnostic principles (no code examples)
- typescript/ extracts TS/JS specifics (Zod, Playwright, Prettier hooks, etc.)
- python/ adds Python rules (PEP 8, pytest, black/ruff, bandit)
- golang/ adds Go rules (gofmt, table-driven tests, gosec, functional options)
- Replace deprecated ultrathink with extended thinking documentation
- Add README.md with installation guide and new-language template

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

* Fix installation commands for rules

Updated installation instructions to copy all rules to a single directory.

* docs: update README.md to reflect new rules directory structure

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

---------

Co-authored-by: Hor1zonZzz <Hor1zonZzz@users.noreply.github.com>
Co-authored-by: Claude Opus 4.5 <noreply@anthropic.com>

rules/typescript/testing.md

@@ -0,0 +1,11 @@
+# TypeScript/JavaScript Testing
+
+> This file extends [common/testing.md](../common/testing.md) with TypeScript/JavaScript specific content.
+
+## E2E Testing
+
+Use **Playwright** as the E2E testing framework for critical user flows.
+
+## Agent Support
+
+- **e2e-runner** - Playwright E2E testing specialist