opentui(phase3): launcher integration — HERMES_TUI_ENGINE dual-engine

hermes --tui launches the native OpenTUI engine (Bun) when
HERMES_TUI_ENGINE=opentui (env) or display.tui_engine=opentui (config);
Ink stays the default and the shipping path is untouched.

- _resolve_tui_engine() (env > config > ink); refuses opentui on
  Windows/Termux (no Bun) -> falls back to ink with a notice.
- _make_opentui_argv() -> [bun, src/entry.real.tsx] (no build step).
- _bun_bin() with HERMES_BUN override.
- Branch at top of _make_tui_argv BEFORE _ensure_tui_node (Bun-only host
  must not bootstrap Node).
- Gate _launch_tui NODE_OPTIONS/--max-old-space-size on engine==ink (Bun
  is JSC; the V8 flag errors/ignores).

Verified end-to-end via tmux: real hermes --tui -> Bun -> OpenTUI ->
real Python gateway streamed a real reply. No-flag default still ink.

website/docs/user-guide/messaging/simplex.md

@@ -54,11 +54,8 @@ SIMPLEX_HOME_CHANNEL=<contact-id>
 | `SIMPLEX_WS_URL` | Yes | WebSocket URL of the simplex-chat daemon |
 | `SIMPLEX_ALLOWED_USERS` | Recommended | Comma-separated allowlist. Each entry can be a numeric `contactId` **or** a display name — both forms work. |
 | `SIMPLEX_ALLOW_ALL_USERS` | Optional | Set `true` to allow every contact (use carefully) |
-| `SIMPLEX_AUTO_ACCEPT` | Optional | Auto-accept incoming contact requests (default: `true`) |
-| `SIMPLEX_GROUP_ALLOWED` | Optional | Comma-separated group IDs the bot participates in, or `*` for any group. Omit to ignore group messages entirely |
-| `SIMPLEX_HOME_CHANNEL` | Optional | Default contact/group ID for cron job delivery |
+| `SIMPLEX_HOME_CHANNEL` | Optional | Default contact ID for cron job delivery |
 | `SIMPLEX_HOME_CHANNEL_NAME` | Optional | Human label for the home channel |
-| `HERMES_SIMPLEX_TEXT_BATCH_DELAY` | Optional | Quiet-period seconds (default: `0.8`) used to concatenate rapid-fire inbound text messages into one event |
 
 ## Find your contact ID or display name
 
@@ -71,37 +68,6 @@ By default **all contacts are denied**. You must either:
 1. Set `SIMPLEX_ALLOWED_USERS` to a comma-separated list of `contactId`s and/or display names (e.g. `SIMPLEX_ALLOWED_USERS=4,alice` matches either contactId 4 or the contact whose display name is "alice"), or
 2. Use **DM pairing** — send any message to the bot and it will reply with a pairing code. Enter that code via `hermes pairing approve simplex <CODE>`.
 
-## Group chats
-
-By default the adapter ignores group messages — a bot in a group otherwise
-processes every member's traffic. Opt-in explicitly:
-
-```
-SIMPLEX_GROUP_ALLOWED=12,34          # specific group IDs
-# or
-SIMPLEX_GROUP_ALLOWED=*              # any group the bot is in
-```
-
-Address groups by prefixing the chat ID with `group:`, e.g.
-`simplex:group:12` in `send_message` or as a cron `deliver=` target.
-
-## Attachments
-
-The adapter supports native SimpleX attachments in both directions:
-
-- **Inbound** — incoming images, voice notes, and files are accepted via
-  the daemon's XFTP flow (`rcvFileDescrReady` → `/freceive` → wait for
-  `rcvFileComplete`) and surfaced as `MessageEvent.media_urls` with the
-  appropriate `MessageType` (`PHOTO`, `VOICE`, `TEXT` + document).
-- **Outbound** — `send_image_file`, `send_voice`, `send_document`, and
-  `send_video` all use the structured `/_send` form with `filePath`, so
-  the receiving SimpleX client renders images inline and plays voice
-  notes inline rather than offering them as downloads.
-
-Agent replies can also embed `MEDIA:/path/to/file` tags in plain text —
-the adapter strips the tag from the body and sends the file as either a
-voice note (audio extensions) or a document.
-
 ## Using SimpleX with cron jobs
 
 ```python