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/common/performance.md

@@ -0,0 +1,55 @@
+# Performance Optimization
+
+## Model Selection Strategy
+
+**Haiku 4.5** (90% of Sonnet capability, 3x cost savings):
+- Lightweight agents with frequent invocation
+- Pair programming and code generation
+- Worker agents in multi-agent systems
+
+**Sonnet 4.5** (Best coding model):
+- Main development work
+- Orchestrating multi-agent workflows
+- Complex coding tasks
+
+**Opus 4.5** (Deepest reasoning):
+- Complex architectural decisions
+- Maximum reasoning requirements
+- Research and analysis tasks
+
+## Context Window Management
+
+Avoid last 20% of context window for:
+- Large-scale refactoring
+- Feature implementation spanning multiple files
+- Debugging complex interactions
+
+Lower context sensitivity tasks:
+- Single-file edits
+- Independent utility creation
+- Documentation updates
+- Simple bug fixes
+
+## Extended Thinking + Plan Mode
+
+Extended thinking is enabled by default, reserving up to 31,999 tokens for internal reasoning.
+
+Control extended thinking via:
+- **Toggle**: Option+T (macOS) / Alt+T (Windows/Linux)
+- **Config**: Set `alwaysThinkingEnabled` in `~/.claude/settings.json`
+- **Budget cap**: `export MAX_THINKING_TOKENS=10000`
+- **Verbose mode**: Ctrl+O to see thinking output
+
+For complex tasks requiring deep reasoning:
+1. Ensure extended thinking is enabled (on by default)
+2. Enable **Plan Mode** for structured approach
+3. Use multiple critique rounds for thorough analysis
+4. Use split role sub-agents for diverse perspectives
+
+## Build Troubleshooting
+
+If build fails:
+1. Use **build-error-resolver** agent
+2. Analyze error messages
+3. Fix incrementally
+4. Verify after each fix