fix: correct package name, install docs, and workspace metadata

[dipankar]

Summary

• Fixes rpytest-daemon not published to PyPI #1
• Fixes rpytest not published to crates.io with rpytest-daemon dependency #6
• Replaced all references to non-existent rpytest-daemon pip package with rpytest (the actual package name)
• Updated cargo install docs to show cargo install rpytest rpytest-daemon and explain both are required
• Migrated crates/rpytest-daemon/Cargo.toml metadata to workspace-inherited fields

Test plan

• Review all doc files for correct package name references
• Verify cargo install docs mention both packages
• Verify rpytest-daemon Cargo.toml uses workspace inheritance