hive-jobq: treat a panicking job runner as a failed node

The future `Scheduler::claim_next` hands back completed its node only
after `run`'s future returned. A panic while running (the workspace
unwinds) skipped that completion, so the node stayed `Running` and its
resource units stayed held until the process restarted; later nodes
needing the same resource never started.

The run future is now polled under `catch_unwind`. A panic completes
the node as `Outcome::Failed("runner panicked: <msg>")` with nothing
grown, through the same `complete_growing` path as an ordinary failure:
`AFTER_OK` dependents are skipped, pending children cascade, and the
node's units are released.

The node's future is boxed: wrapping it inline pushed the futures
swarm-controller and hive-c0re spawn over clippy's `large_futures`
limit.

Closes #5058

hive-jobq/README.md

@@ -59,7 +59,8 @@ finished_at, error }`. All fields public; derives serde for the wire
   (acquiring resources atomically), `complete(id, outcome)` reports a finished
   node's result and rolls terminality up the parent chain, releasing grants once
   a subtree is done. `Outcome::{Done, Failed(String)}` — the failure reason
-  rides `Failed` onto the node's `error`.
+  rides `Failed` onto the node's `error`. A runner that panics completes its node as
+  `Failed` with the panic message, which releases its grants like any failure.
 - **`ResourceTable<R>`** — per-name capacities; unconfigured names default to
   capacity 1.