⚙️ Drop Python 3.8 and 3.9 support, and update CI coverage to Python 3.10 through 3.14.

[acabarbaye]

Summary

• raise the declared Python support floor from 3.8 to 3.10
• update CI and release workflows to exercise Python 3.10 through 3.14
• fix the deprecated unittest assertion so the test suite still runs on Python 3.14

Why this change

The recent dependency update means the project can no longer resolve its environment on Python 3.8.

pipenv lock now pulls packages whose current releases require newer Python versions, including dependencies that declare Requires-Python >=3.10. As a result, the CI lock step fails on Python 3.8 before tests even run.

Because the project currently follows floating dependency resolution for several packages, keeping Python 3.8 or 3.9 support would require adding and maintaining older version pins specifically for those interpreters. This change instead aligns the declared support range with the dependency set that resolves today.

Validation

• confirmed pipenv lock --dev succeeds on Python 3.14
• updated package metadata and the CI matrix to advertise and test Python 3.10 through 3.14
• ran pytest on Python 3.14 and fixed the deprecated �ssertNotEquals usage exposed there