refactor: replace darker with ruff in pre-commit hook (#100)

* refactor: replace darker with ruff in pre-commit hook

Replace the darker pre-commit hook with ruff for better performance
and enhanced features. This replaces darker, black, flake8, flynt,
isort, and pylint with ruff's linter and formatter.

- Use ruff-pre-commit (v0.15.7) with ruff and ruff-format hooks
- Add "I" (isort) rule to ruff lint config in pyproject.toml
- Preserve file scope to nepali/ and tests/ directories

Closes #99

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* refactor: centralize file scope in pyproject.toml

- Remove `files` directive from ruff pre-commit hooks
- Add `tests/**/*.py` to ruff include pattern in pyproject.toml
- File scoping now handled entirely by ruff config

---------

Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.pre-commit-config.yaml

@@ -9,24 +9,12 @@ repos:
       - id: end-of-file-fixer
       - id: trailing-whitespace
 
-  - repo: https://github.com/akaihola/darker
-    rev: v2.1.1
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.15.7
     hooks:
-      - id: darker
-        files: ^(nepali/|tests/)
-        args:
-          - --isort
-          - --flynt
-          - --lint=flake8 --max-line-length=88 --ignore=E203,W503
-          - --lint=mypy # --strict # commenting strict for now as we haven't maintained typing completely
-          - --lint=pylint --max-line-length=88 --disable=W0511
-        additional_dependencies:
-          - black==26.1.0
-          - flake8==7.3.0
-          - flynt==1.0.6
-          - isort==7.0.0
-          - mypy==1.19.1
-          - pylint==4.0.4
+      - id: ruff
+        args: [--fix]
+      - id: ruff-format
 
   - repo: https://github.com/opensource-nepal/commitlint
     rev: v1.13.3

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.ruff]
 line-length = 127
-include = ["nepali/**/*.py", "pyproject.toml"]
+include = ["nepali/**/*.py", "tests/**/*.py", "pyproject.toml"]
 
 [tool.ruff.lint]
-select = ["E", "W", "F"]
+select = ["E", "W", "F", "I"]