Fix CI: add pytest-cov, pip cache, update Python version requirement

Co-authored-by: justinmstuart <1878176+justinmstuart@users.noreply.github.com>

Author: Copilot

.github/workflows/tests.yml

@@ -21,6 +21,7 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: '3.12'
+          cache: 'pip'
 
       - name: Install dependencies
         run: pip install -r requirements.txt

README.md

@@ -14,7 +14,7 @@ Scripts are fully tested, linted, and compatible with both direct execution and
 
 ## Requirements
 
-- Python 3.6+
+- Python 3.12+
 
 ## Getting Started
 

requirements.txt

@@ -2,4 +2,5 @@ Pillow
 mutagen
 pylint
 pytest
+pytest-cov
 python-dotenv