feat: Implement workspace rename cli (#3209)

* feat(cli): add workspace rename command

`paseo workspace rename <workspace-id> <title>` sets a workspace's
user-visible title through the existing workspace.title.set RPC, and
`--reset` clears the override so the name reverts to the branch or
directory. The command reads the descriptor back so the output shows
what a reset reverted to.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* fix(cli): harden workspace rename against read-back and arg failures

Review findings on the rename command:

- A failed workspace list sweep after a successful title change reported
  the whole command as failed. The read-back is display-only, so it now
  runs outside the mutation's error path and degrades to a null name.
- Only --reset needs the descriptor read back; a set title is already the
  resolved display name, so the common path no longer pages the list.
- Dropped the `"code" in error` rethrow. Nothing in that block throws a
  CommandError, but DaemonRpcError always carries a `code` property even
  when it is undefined, so the guard let those through to render as
  UNKNOWN_ERROR with a stack instead of WORKSPACE_RENAME_FAILED.
- Commander 12 allows excess positionals, so an unquoted multi-word title
  renamed to its first word and dropped the rest. The command now rejects
  excess arguments.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

* refactor(cli): report the rename RPC response instead of reading back

Reading the descriptor back to show what --reset reverted to was the only
reason rename needed a paged workspace sweep, and that sweep dragged in
everything around it: a failure path that could report an applied rename
as failed, a nullable name, and a bespoke warning sink to tell the two
null cases apart.

Sibling commands don't do this. `workspace archive`, `agent mode`, and
`schedule update` all report what the RPC returned and stop; the one
command that reads back is `agent update`, which has the same "applied
but reported as failed" bug. So rename now mirrors `workspace archive`.

`--reset` reports `title: null` rather than naming what it reverted to;
`paseo workspace ls` shows the resolved name. This also reverts the
`collectWorkspaces` extraction, whose only second caller was rename.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

docs/architecture.md

@@ -121,7 +121,7 @@ Commander.js CLI with Docker-style commands. Common agent operations are also ex
 - `paseo script ls/start/stop`
 - `paseo schedule create/ls/inspect/update/pause/resume/run-once/logs/delete`
 - `paseo heartbeat create/update/delete`
-- `paseo workspace create/ls/archive`
+- `paseo workspace create/ls/rename/archive`
 - `paseo permit allow/deny/ls`
 - `paseo provider ls/models`
 - hidden legacy `paseo worktree create/ls/archive` compatibility alias