feat(assets): copy project-relative paths

[SuperSuperPepper]

Assisted-by: OpenAI GPT-5

Summary

Adds a Copy Path action to the Asset Browser context menu.

Changes

• Adds Copy Path for files and folders
• Copies a project-relative path with forward slashes
• Updates the asset pipeline documentation and release notes

Related Issues

Closes #108

AI Assistance

Assisted-by: OpenAI GPT-5

Checklist

• Code compiles cleanly (renzora check)
• All existing tests pass (renzora test)
• New tests added (if applicable)
• No unrelated formatting or refactoring changes
• Branch is up to date with main
• I have read every line of this diff and can explain it in review
• Any AI assistance is disclosed above and in an Assisted-by: commit trailer

Testing

• cargo clippy --profile dist -p renzora_asset_browser --no-deps -- -D warnings -A clippy::too_many_arguments -A clippy::type_complexity
• cargo test --profile dist -p renzora_asset_browser --lib
• Manually verified Copy Path in the Asset Browser

[RenzoraEngine]

Merged, thank you! Tested it locally before it went in and it does exactly what it says.

Nice touch picking the project-relative form with forward slashes rather than the OS path: that is the shape scenes, scripts and material references all use, so what lands on the clipboard is something you can paste straight into one. Slotting it between Duplicate and Reveal is the right spot too.

The only thing I had to touch was RELEASE_NOTES.md, and that was my fault rather than yours: the ## Unreleased section became per-change timestamped headings a couple of hours after you cut the branch, so your line just moved to a heading of its own. Nothing to do on your side.

Thanks again, and please do send more.