feat: Add SOLID principles and TDD reference documentation

- Created solid.md to document the SOLID principles for clean code practices.
- Created tdd.md to outline Test Driven Development principles and practices.
- Added kana-rust-backend-best-practice.md as a reference guide for building a Rust backend using Axum and SeaORM.
- Established push-flow-convention.md to enforce pre-commit and pre-push hooks with versioning rules.
- Introduced AGENTS.md to provide guidance on best practices and available commands for Kilo.
- Configured kilo.json to include new skills and agents for enhanced functionality.
- Added lefthook.yml for managing git hooks to ensure code quality and adherence to conventions.

apps/interfaces/web/src/lib.rs

@@ -83,7 +83,7 @@ async fn static_handler(
                 .status(200)
                 .header("Content-Type", mime.to_string())
                 .body(axum::body::Body::from(data))
-                .unwrap()
+                .expect("Response builder with known-valid status and header")
                 .into_response()
         }
         Err(_) => (StatusCode::NOT_FOUND, "Not found").into_response(),