Introduce pre-commit hooks and update contribution guidelines

- Add `.pre-commit-config.yaml` with hooks for formatting, linting, and general file checks.
- Update `CONTRIBUTING.md` to include pre-commit setup instructions and emphasize automated checks during commits.
- Provide detailed steps for installing and running pre-commit hooks.

.pre-commit-config.yaml

@@ -0,0 +1,34 @@
+# Pre-commit hooks configuration
+# See https://pre-commit.com for more information
+
+repos:
+  # General file checks
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v5.0.0
+    hooks:
+      - id: trailing-whitespace
+      - id: end-of-file-fixer
+      - id: check-yaml
+      - id: check-toml
+      - id: check-merge-conflict
+      - id: check-added-large-files
+        args: ['--maxkb=1000']
+      - id: mixed-line-ending
+
+  # Rust formatting
+  - repo: https://github.com/doublify/pre-commit-rust
+    rev: v1.0
+    hooks:
+      - id: fmt
+        name: cargo fmt
+        description: Format Rust code with rustfmt
+      - id: cargo-check
+        name: cargo check
+        description: Check Rust code compilation
+      - id: clippy
+        name: cargo clippy
+        description: Lint Rust code with clippy
+        args: ['--all-features', '--', '-D', 'warnings']
+
+# Optional: run on all files when config changes
+default_install_hook_types: [pre-commit, pre-push]