chore: upgrade Python version from 3.10 to 3.13 across the project

Agent-Logs-Url: https://github.com/christianlouis/dmarq/sessions/29bd6108-4094-48ca-8976-10df52774551

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>

pyproject.toml

@@ -4,7 +4,7 @@ version = "1.6.0"
 description = "A modern, privacy-conscious DMARC monitoring and analysis platform"
 readme = "README.md"
 license = {text = "MIT"}
-requires-python = ">=3.10"
+requires-python = ">=3.13"
 
 [tool.semantic_release]
 version_toml = ["pyproject.toml:project.version"]
@@ -22,7 +22,7 @@ match = "main"
 
 [tool.black]
 line-length = 100
-target-version = ['py310']
+target-version = ['py313']
 include = '\.pyi?$'
 extend-exclude = '''
 /(
@@ -99,7 +99,7 @@ show_missing = true
 skip_covered = false
 
 [tool.mypy]
-python_version = "3.10"
+python_version = "3.13"
 warn_return_any = true
 warn_unused_configs = true
 disallow_untyped_defs = false