Problem

There is no way to change the ticket ID associated with a workspace after creation. This is a common need (wrong ticket ID, ticket split, etc.).

Proposed Solution

Add parsec rename <old-ticket> <new-ticket> that:

1. Updates workspace state (.parsec/state.json)
2. Renames the git branch (feature/old → feature/new)
3. Records the rename in oplog
4. Optionally updates the remote branch name

Category: feature | Priority: low