fix(cli): review — 8-char id floor, marker echo, wake answers on send

From the review of #557:

- An id shorter than 8 characters refuses with exit 4 before any request,
  on every verb. `rm 9` resolved to whichever session was alone with that
  first character (the user's own tab included) and deleted it. Same floor
  as the server's PARENT_SESSION_ID_MIN_PREFIX. `rm` no longer claims a
  lineage check: "Delete any session except this one".
- `wait --match` help and the README example say the marker must not appear
  verbatim in the prompt (its echo matches at once) and show the split form.
- `send` reads the route's wake-on-LAN answers: `buffered` gets its own
  line (exit 0), `dropped` exits 1 instead of printing "accepted".
- `--` for a prompt that starts with "-", in the `send` description and in
  the one-argument refusal.
- `stripAnsi` builds on the shared one (OSC sequences go too); the
  inputRefusal JSDoc sits above inputRefusal again.
- docs/wiki/Driving-Codeman-From-An-Agent.md gets a `codeman agent` section.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

README.md

@@ -954,12 +954,13 @@ SID=$(codeman agent spawn scratch-1 --mode claude)        # quick-start + wait f
 codeman agent send "$SID" 'review src/, then say DONE' --until stop,exit --timeout 300000   # --wait = default signal set
 codeman agent read "$SID"                                 # last answer (as the server reads it for that mode)
 codeman agent read "$SID" --tail 3000                     # terminal tail, ANSI stripped (every mode)
-codeman agent wait "$SID" --match DONE_4711               # marker wait for hook-less modes (opencode, pi, …)
+codeman agent send "$SID" 'run the tests, then print WORKDONE followed by _4711'   # hook-less modes (opencode, pi, …): ask for the marker in halves …
+codeman agent wait "$SID" --match WORKDONE_4711           # … and wait on the joined form, which the prompt's echo never contains
 codeman agent interrupt "$SID"                            # a bare ESC, conversation intact
-codeman agent rm "$SID"                                   # refuses your own id
+codeman agent rm "$SID"                                   # any session except this one
 ```
 
-Rules the commands enforce rather than document: they refuse outside a Codeman session and never guess a URL; `send` transmits printable text plus Enter only (a control byte such as `Ctrl+C` is `app_exit` in opencode — ESC exists solely as `interrupt`, which never appends Enter); `rm` refuses an empty id, an unprovable self id and a prefix match in either direction. Ids may be the 8-character prefixes `ls` prints (resolved through the list; an ambiguous prefix refuses). Exit codes: `0` delivered/matched/signal, `1` error, `2` timeout, `3` the worker exited or the wait ended without an answer (`delivered:false`, `ended:true`), `4` refused. `spawn` prints the id alone on stdout (prose goes to stderr), so `SID=$(…)` captures exactly the id. `--json` prints the envelope's `data` for every verb. `--until stop` on a mode without hook signals is the server's 400, passed through — the marker path (`--match`) is the answer there, exactly as for the skill.
+Rules the commands enforce rather than document: they refuse outside a Codeman session and never guess a URL; `send` transmits printable text plus Enter only (a control byte such as `Ctrl+C` is `app_exit` in opencode — ESC exists solely as `interrupt`, which never appends Enter); `rm` refuses an empty id, an unprovable self id and a prefix match in either direction. Ids may be the 8-character prefixes `ls` prints (resolved through the list; an ambiguous prefix refuses, anything shorter than 8 characters refuses on every verb). A prompt that starts with `-` goes after `--` (`send "$SID" -- "- fix the bug"`). The echo of the prompt you sent is output too: a `--match` marker that appears verbatim in the prompt matches at once, before the worker has done anything, so the prompt asks for it in halves. A remote session whose host is asleep answers a fire-and-forget `send` with `buffered` (Codeman wakes the host and types the prompt once the pane is back) or `dropped` (over the wake buffer's cap, nothing will be typed: exit `1`). Exit codes: `0` delivered/matched/signal, `1` error, `2` timeout, `3` the worker exited or the wait ended without an answer (`delivered:false`, `ended:true`), `4` refused. `spawn` prints the id alone on stdout (prose goes to stderr), so `SID=$(…)` captures exactly the id. `--json` prints the envelope's `data` for every verb. `--until stop` on a mode without hook signals is the server's 400, passed through — the marker path (`--match`) is the answer there, exactly as for the skill.
 
 ### Hooks (events flowing _back_ to Codeman)