chore: sync versions and workaround auto-version-action bug

[dgaida]

This PR syncs the version numbers across pyproject.toml and llm_client/__init__.py to 0.4.8. It also applies a workaround for a bug in the dgaida/auto-version-action GitHub Action.

The action uses a brittle grep '^version = "' to extract the version. When multiple matches are found (e.g., in both [project] and [tool.commitizen] sections), it fails to create a valid tag. By formatting the commitizen version entry without spaces (version="0.4.8"), we prevent the action from matching it, thus resolving the fatal: Failed to resolve '0.4.7' as a valid ref. error.

Changes:

• Synced version to 0.4.8 in pyproject.toml and llm_client/__init__.py.
• Formatted [tool.commitizen].version to avoid action grep bug.
• Added v0.4.8 entry to CHANGELOG.md.

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PR created automatically by Jules for task 13901189175860617068 started by @dgaida

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