fix: sync Tauri release versions

[jeremymcs]

Summary

• add Release Please extra-files for Tauri config, Cargo manifest, and Cargo lock package version
• update Tauri metadata to match the current 1.3.0 package version
• add a regression test that keeps release metadata and Tauri versions in sync

Tests

• node --import tsx --test server/appBranding.test.ts
• npm run check
• npm run test

[github-actions]

📄 Documentation Review Reminder

This PR changes source files but does not update any public documentation.

Changed source files:

server/appBranding.test.ts

Please check if documentation in docs/public/ needs to be updated:

• No documentation update needed
• Documentation updated in this PR
• Follow-up documentation issue created

Public docs are Markdown files in docs/public/. They are automatically
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Available docs: getting-started.md, pr-babysitter.md, agent-dispatch.md, configuration.md, pr-questions.md