Let outside services and computers' browser notifications give bots work

A bot hook (bot_hooks) is a secret URL, POST /api/hooks/<token>, whose
calls queue the hook's brief plus the raw body as a task, per user and
bot like a routine. Only the token's hash is kept (shown once, rotatable);
an optional HMAC-SHA256 signing secret is stored encrypted. Calls are
rate limited per address and per hook, recorded in bot_hook_events
(pruned daily), deduplicated by delivery id, and a call while the last
run still waits joins its brief instead of queueing another. The payload
is fenced data and HookRunNote tells the bot never to take instructions
from it; failed runs retry like routines.

A hook can instead watch a computer's browser notifications: the app
installs a small watcher that owns org.freedesktop.Notifications on the
sandbox's session bus, so Chrome hands it every notification (it only
looks for that service at start-up, so Chrome is restarted once, never
mid-task), and it posts each one to its hooks, optionally filtered.
Computers reach the app at COMPUTER_APP_URL or the app container's name.

Users make hooks in the conversation's Hooks modal and manage them all
on /admin/routines; bots never create or change hooks.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/dict/env-dict.ts

@@ -66,6 +66,12 @@ export const EnvDict: readonly KnownEnv[] = [
         required: false,
         secret: false,
     },
+    {
+        key: "COMPUTER_APP_URL",
+        description: `Where computers reach this app, for hooks they call (browser notifications), e.g. http://172.17.0.1:7000 for a server running outside docker. Empty uses the app's container on the docker network.`,
+        required: false,
+        secret: false,
+    },
     {
         key: "MAIN_COMPUTER_DATA_DIR",
         description: `Where the main computer's workspace (/home/gem/workspace, the only folder bots work in) is on this server's disk, for a computer the app didn't create itself (see MAIN_COMPUTER_URL), e.g. the bind mount your sandbox's compose file uses. Empty reads DATA_DIR/computers/<id>.`,