fix: align release-plz config with new schema

[behrangsa]

Summary

• drop the legacy [package.version] and [package.semver] tables that release-plz 0.3.146 no longer accepts (per https://release-plz.dev/docs/config)
• keep the workspace/package/changelog settings intact so release-plz can still generate our changelog and PR text

Testing

• cargo fmt --check
• cargo clippy --all-targets --all-features
• cargo test -- --test-threads=1
• release-plz release-pr --config .release-plz.toml (halts only to ask for --git-token, confirming config parses)

[Copilot]

Pull Request Overview

This PR updates the .release-plz.toml configuration file to comply with the new schema requirements of release-plz 0.3.146. The update removes deprecated configuration sections while preserving essential changelog and workspace functionality.

• Removes deprecated [package.version] and [package.semver] tables that are no longer supported
• Migrates git-cliff configuration from [package.git_cliff] to the top-level [changelog] section
• Updates regex patterns and template syntax for compatibility with the new schema

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[github-actions]

📊 Coverage Report

Metric	Covered	Total	Rate
Lines	131	146	89.73%
Branches	0	0	N/A

Additional Metric	Value
Complexity	0
Files Reported	1
Report Timestamp	2025-09-24T21:34:57.000Z

View detailed report

src/main.rs: 89.7%

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