Add pre-commit with ruff, mypy, and standard hooks

- ruff check + format with ALL rules (ignoring D, ANN, FBT, T201)
- mypy strict mode with pydantic plugin
- Standard pre-commit hooks (trailing whitespace, end-of-file, etc.)
- Fix all type annotations for strict mypy compliance

.pre-commit-config.yaml

@@ -0,0 +1,27 @@
+repos:
+  - 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-added-large-files
+      - id: check-merge-conflict
+      - id: debug-statements
+
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.8.4
+    hooks:
+      - id: ruff
+        args: [--fix]
+      - id: ruff-format
+
+  - repo: https://github.com/pre-commit/mirrors-mypy
+    rev: v1.14.0
+    hooks:
+      - id: mypy
+        additional_dependencies:
+          - pydantic>=2.0.0
+          - typer>=0.9.0
+          - asyncssh>=2.14.0
+          - types-PyYAML