feat: add comprehensive skills and agents for Rust development (#1573)

.claude/skills/coding-guidelines/clippy-lints/_index.md

@@ -0,0 +1,16 @@
+# Clippy Lint → Rule Mapping
+
+| Clippy Lint | Category | Fix |
+|-------------|----------|-----|
+| `unwrap_used` | Error | Use `?` or `expect()` |
+| `needless_clone` | Perf | Use reference |
+| `await_holding_lock` | Async | Scope guard before await |
+| `linkedlist` | Perf | Use Vec/VecDeque |
+| `wildcard_imports` | Style | Explicit imports |
+| `missing_safety_doc` | Safety | Add `# Safety` doc |
+| `undocumented_unsafe_blocks` | Safety | Add `// SAFETY:` |
+| `transmute_ptr_to_ptr` | Safety | Use `pointer::cast()` |
+| `large_stack_arrays` | Mem | Use Vec or Box |
+| `too_many_arguments` | Design | Use struct params |
+
+For unsafe-related lints → see `unsafe-checker` skill.