refactor: switch to hooks for linting

[Dev-iL]

Description

Replace the legacy linting toolchain (black, flake8, flake8-import-order) with ruff and switch CI from running individual lint commands to prek (a Rust-based pre-commit runner) executing hooks defined in .pre-commit-config.yaml.

What changed:

• Ruff now handles both linting (ruff check, replacing flake8 + flake8-import-order) and formatting (ruff format, replacing black). Mypy is kept as-is since ruff does not cover type checking.
• prek replaces the ad-hoc pip install + manual invocation approach in CI with a single prek run --all-files step.
• Added .pre-commit-config.yaml with ruff and mypy hooks.
• Added [tool.ruff] configuration in pyproject.toml, matching the previous flake8 settings (line-length 90, same excludes, google-style import ordering via isort rules).
• Removed [flake8] section from setup.cfg, removed [testenv:flake8] and [testenv:black] from tox.ini.
• Updated requirements/dev.in: dropped black, flake8, flake8-import-order; added ruff and prek.
• Auto-fixed ~62 import ordering issues and reformatted ~31 files to match ruff's formatter output.
• Added per-file-ignores for pre-existing E721 and F811 violations to keep the migration clean.

Note regarding mypy

The 3 failing modules (validators, models.sqla, models.sqla.interface) now have ignore_errors = true with TODO comments. The old CI never actually checked them due to the broken glob, so this matches the prior behavior. The type errors can be fixed in a follow-up.

  flask_appbuilder/models/sqla/__init__.py:11: error: Variable "flask_appbuilder.models.sqla.Base" is not valid   
as a type  [valid-type]                                                                                           
  flask_appbuilder/models/sqla/__init__.py:11: note: See                                                          
https://mypy.readthedocs.io/en/stable/common_issues.html#variables-vs-type-aliases                                
  flask_appbuilder/models/sqla/__init__.py:11: error: Invalid base class "Base"  [misc]                           
  flask_appbuilder/validators.py:45: error: "BaseInterface" has no attribute "FilterEqual"  [attr-defined]        
  flask_appbuilder/models/sqla/interface.py:52: error: Incompatible types in assignment (expression has type      
"type[SQLAFilterConverter]", base class "BaseInterface" defined the type as "<typing special form>")              
[assignment]                                                                                                      
  flask_appbuilder/models/sqla/interface.py:584: error: "str" has no attribute "all"  [attr-defined]              
  flask_appbuilder/models/sqla/interface.py:593: error: "str" has no attribute "all"  [attr-defined]              
  flask_appbuilder/models/sqla/interface.py:602: error: "str" has no attribute "all"  [attr-defined]              
  flask_appbuilder/models/sqla/interface.py:967: error: Incompatible default for argument "list_columns" (default 
 has type "None", argument has type "list[str]")  [assignment]                                                    
  flask_appbuilder/models/sqla/interface.py:967: note: PEP 484 prohibits implicit Optional. Accordingly, mypy has 
 changed its default to no_implicit_optional=True                                                                 
  flask_appbuilder/models/sqla/interface.py:967: note: Use https://github.com/hauntsaninja/no_implicit_optional   
to automatically upgrade your codebase                                                                            
  flask_appbuilder/models/sqla/interface.py:1033: error: "SQLAInterface" has no attribute "FilterEqual"           
[attr-defined]                                                                                                    
  flask_appbuilder/models/sqla/interface.py:1035: error: "SQLAInterface" has no attribute "FilterEqual"           
[attr-defined]                                                                                                    
  Found 10 errors in 3 files (checked 90 source files) 

ADDITIONAL INFORMATION

• Has associated issue:
• Is CRUD MVC related.
• Is Auth, RBAC security related.
• Changes the security db schema.
• Introduces new feature
• Removes existing feature