Add project status and MVP assessment

[Copilot]

For Tom

Doshell has a substantial v1.10 alias set and installer, but no automated tests, and its documented Dash support fails a syntax check. STATUS.md summarizes the current state and path to a usable first version. Needs your answer: Which shells should the first version support?

• Assessment: Documents what works, what remains, and the current build, run, and test status.
• MVP path: Lists focused next steps for choosing shell support, checking installation, and aligning documentation.
• Decision: Recommends Bash-first; records the alternative of supporting and testing Bash, Zsh, and Dash/Ash.
• Security: Notes an author email in historical commit metadata without reproducing it.

• Fixes Status review: how close is this to a usable first version? #1