* feat(linear): edit and delete Linear comments from the CLI
Adds orca linear comment edit <commentId> and orca linear comment delete <commentId>
(alias rm). The comment id alone names the comment; Orca finds the connected workspace
that owns it unless --workspace is given. Both refresh a linked worktree's issue and
report unconfirmed writes with a read-back step. The orca-linear guide documents them.
* test(linear): use a checked linked worktree fixture
* fix(linear): bound and cancel comment actions
