fix: validate installed release version

[pitill0]

Summary

Fix the release workflow version check used after installing the generated wheel.

Problem

fluxtuner --version prints the user-facing string:

FluxTuner 1.0.7

The release workflow compared that output directly with the tag-derived value:

1.0.7

As a result, the wheel installed successfully but the release job failed during the version assertion.

Changes

• Validate the installed package version through importlib.metadata.
• Compare the installed fluxtuner package version with the release tag without relying on CLI formatting.
• Keep fluxtuner --version as a normal smoke test.
• Preserve the existing help, player and theme diagnostics.

Validation

• Confirmed the generated wheel installs successfully.
• Confirmed the installed package metadata reports 1.0.7.
• Confirmed fluxtuner --version prints FluxTuner 1.0.7.