⬆️ UPGRADE: Support mdformat v1 and Python >=3.10

[KyleKing]

Closes: #12

• Drop Python 3.7, 3.8, and 3.9
• Support mdformat v1
• Includes some much needed updates that overlap with ci: update latest ci and secure publish #9

[Copilot]

Pull Request Overview

This PR modernizes the project by dropping support for Python 3.7-3.9 and adopting mdformat v1 with Python 3.10+ as the minimum requirement.

• Updated Python support from 3.7-3.10 to 3.10 and 3.13 only
• Upgraded mdformat dependency from <0.8.0 to >=0.7.0 (v1 support)
• Updated all development dependencies and GitHub Actions to modern versions

Reviewed Changes

Copilot reviewed 6 out of 7 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
tox.ini	Updated test environments to support only Python 3.10 and 3.13
pyproject.toml	Bumped minimum Python version to 3.10 and updated dependency versions
README.md	Updated documentation examples to use Python 3.10 instead of 3.9
.pre-commit-config.yaml	Updated pre-commit hooks to latest versions with modern dependency specifications
.github/workflows/tests.yml	Updated GitHub Actions to use latest versions and Python 3.10/3.13 matrix
.github/dependabot.yml	Changed dependency update frequency from daily to monthly

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