Add computer switching, crew reporting, job steps and markdown chat

- Bots have a current computer (bots.computer_id), switched from the chat
  header beside the model button or by clicking a computer the bot names
  ([computer:ID]); tasks run on it by default
- search_computers runs one read-only command on all of a bot's computers;
  chat replies know their computers (compose-computers-note)
- The coordinator can use every computer and grants or revokes crew access
  with assign_computer
- Delegated jobs record requested_by_bot_id; the worker's result or failure
  is reported back in the coordinator's conversation
- bots_queue_updates records each model turn of a job, pushed live and shown
  in the working-on panel
- Live relay: every process pushes new messages, job steps and bot changes
  from the database to its own sockets, so work done elsewhere shows live
- Bot messages render as markdown (react-markdown + remark-gfm, no raw HTML)
  with twui components; rail previews are plain text
- Fix header button overflow in the model and computer selects
- Bump @moduletrace/twui to 0.1.2

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

src/utils/link-computer-refs.ts

@@ -0,0 +1,18 @@
+/**
+ * The link target a computer ref (`computerRef`) becomes, e.g.
+ * `#computer-3`. The chat's markdown renders these links as buttons that
+ * switch the bot to that computer.
+ */
+export const ComputerRefHrefPrefix = "#computer-";
+
+/**
+ * Turns every computer ref in a message into a markdown link to
+ * `#computer-<id>`, so it survives markdown rendering as a link the chat
+ * can swap for a switch button.
+ */
+export default function linkComputerRefs({ text }: { text: string }) {
+    return text.replace(
+        /\[computer:(\d+)\](?!\()/g,
+        (_, id: string) => `[computer ${id}](${ComputerRefHrefPrefix}${id})`,
+    );
+}