docs(discord): write down the lone-digit rule, which installs have codeman, and tidy comments

- lone digit rule in CLAUDE.md, invariants, user docs, wiki, API reference and code comments
- say which installs have the codeman command
- reload() comment back above reload(), merge the sendInput comments, typedHint in the hint comment
- drop the stray dot after --urgent in the startup hint
- config-backups wiki: name the discord.json token, not the URL
- comma in the CLAUDE.md auto-named list

docs/api-reference.md

@@ -1497,7 +1497,7 @@ One thread per tab in a private Discord channel, alerts out and replies typed ba
 | `POST` | `/api/discord/test` | none | Posts one message to the parent channel with the saved config, even while disabled. `200` with `data.ok`; `400` if no token or channel is saved. |
 | `POST` | `/api/sessions/:id/discord-notify` | `{ message, urgent?, file? }` (strict, message 1 to 1500 characters) | A CLI asks for the user: posts into that tab's thread, pinging when `urgent`. `file` is an absolute path inside the tab's working folder (real path, regular file, at most 8 MB, local sessions only) uploaded with the post; `400` otherwise. A `200` carries the delivery result: `data.ok` is `false` (with `data.error`) when Discord refused or failed the post. `409` while the bridge is disabled, `429` past 6 posts a minute per tab. The `codeman notify "message" [--urgent] [--file path]` command wraps this route. |
 
-Only replies from `allowedUserIds`, in `guildId`, inside a thread the bridge created are typed into a session, as one printable line plus Enter, at most one per second per tab. Attached files are saved under `.codeman-discord/` in the tab's folder and their paths appended to that line (see [discord-bridge.md](discord-bridge.md)).
+Only replies from `allowedUserIds`, in `guildId`, inside a thread the bridge created are typed into a session, as one printable line plus Enter (a lone digit while a permission or question is pending goes as the key alone), at most one per second per tab. Attached files are saved under `.codeman-discord/` in the tab's folder and their paths appended to that line (see [discord-bridge.md](discord-bridge.md)).
 
 ## Diagnostics