Tell replies their envs and call queued work runs

Chat replies now list the envs that reach them (keys and descriptions,
never values), so a bot no longer asks for keys that are set or "checks"
them with show_secret or printenv. request_secret refuses a key that's
already set unless the user asked to replace it, and search_computers
says envs aren't loaded in its shell.

start_task and delegate_task results say "Run #N" and that list_tasks
doesn't show it, since bots sent users to the to-do list for queue jobs.
start_task refuses a second open run in the session on the same
computer unless it's separate work, and says how many runs are ahead on
that computer.

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

src/functions/backend/db/bots-queue/count-computer-task-jobs.ts

@@ -0,0 +1,24 @@
+import BunSQLite from "@moduletrace/bun-sqlite";
+
+type Params = {
+    computer_id: number | string;
+    /**
+     * Left out of the count, e.g. the job just queued.
+     */
+    except_job_id?: number | string | null;
+};
+
+/**
+ * How many tasks are queued or working on a computer (any bot's, any
+ * user's). Tasks run one at a time per computer, so a new one waits for
+ * all of them.
+ */
+export default async function countComputerTaskJobs({ computer_id, except_job_id }: Params) {
+    const res = await BunSQLite.sql<{ n: number }>({
+        sql: `SELECT COUNT(*) AS n FROM bots_queue
+            WHERE computer_id = ? AND kind = 'task' AND status IN ('pending', 'processing') AND id != ?`,
+        values: [Number(computer_id), Number(except_job_id) || 0],
+    });
+
+    return Number(res.payload?.[0]?.n) || 0;
+}