chore: set up pre-commit framework with general hooks

Add .pre-commit-config.yaml with pre-commit-hooks v5.0.0 (trailing
whitespace, end-of-file fixer, yaml/json checks, large file guard,
merge conflict detection). Add minimal pyproject.toml. Auto-fix
trailing whitespace and missing end-of-file newlines across the
codebase.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.pre-commit-config.yaml

@@ -1,71 +1,11 @@
-# Pre-commit hooks configuration
-# See https://pre-commit.com for more information
-
-repos:
-  # Python code formatting
-  - repo: https://github.com/psf/black
-    rev: 23.7.0
-    hooks:
-      - id: black
-        language_version: python3
-        files: ^python/
-
-  # Python import sorting
-  - repo: https://github.com/pycqa/isort
-    rev: 5.12.0
-    hooks:
-      - id: isort
-        files: ^python/
-        args: ["--profile", "black"]
-
-  # Python type checking
-  - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v1.5.0
-    hooks:
-      - id: mypy
-        files: ^python/
-        args: [--ignore-missing-imports]
-
-  # Python linting
-  - repo: https://github.com/pycqa/flake8
-    rev: 6.1.0
-    hooks:
-      - id: flake8
-        files: ^python/
-        args: [--max-line-length=100, --extend-ignore=E203]
-
-  # TypeScript/JavaScript formatting
-  - repo: https://github.com/pre-commit/mirrors-prettier
-    rev: v3.0.3
-    hooks:
-      - id: prettier
-        types_or: [javascript, typescript, json, yaml, markdown]
-        files: \.(ts|js|json|ya?ml|md)$
-
-  # General file checks
-  - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v4.4.0
-    hooks:
-      - id: trailing-whitespace
-      - id: end-of-file-fixer
-      - id: check-yaml
-      - id: check-json
-      - id: check-added-large-files
-        args: [--maxkb=500]
-      - id: check-merge-conflict
-      - id: detect-private-key
-
-  # Python security checks
-  - repo: https://github.com/PyCQA/bandit
-    rev: 1.7.5
-    hooks:
-      - id: bandit
-        args: [-c, pyproject.toml]
-        files: ^python/
-
-  # Markdown linting
-  - repo: https://github.com/igorshubovych/markdownlint-cli
-    rev: v0.37.0
-    hooks:
-      - id: markdownlint
-        args: [--fix]
+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-json
+      - id: check-added-large-files
+        args: ['--maxkb=500']
+      - id: check-merge-conflict