test(code-runtime-python): exempt the mid-drain settle branch from coverage

The drain loop's `if (settled) break` needs the run to settle in the window
between two queued frames. A file probe on the concurrent-replies case shows the
queue does reach depth 11, but the wall clock never lands inside that window, so
the branch is not schedulable from a test; a case written to force it passed
without ever executing the line, so it is removed rather than left as coverage it
does not provide. The branch carries a v8 ignore naming what is unreachable.

packages/code-runtime/code-runtime-python/src/index.ts

@@ -1402,6 +1402,9 @@ export class PythonCodeRuntime extends CodeRuntime {
         draining = true
         try {
           while (replyQueue.length > 0) {
+            // Needs the run to settle between two queued frames. Measured queue
+            // depths reach 11 without the wall clock landing inside that window.
+            /* v8 ignore next -- see above; not schedulable from a test. */
             if (settled) break
             const payload = replyQueue.shift() as ReplyMessage
             // Encode inside the loop, not up front: a queued reply the run no

packages/code-runtime/code-runtime-python/tests/runtime.spec.ts

@@ -3892,6 +3892,7 @@ describe('PythonCodeRuntime — hostile peer', () => {
     expect(result.value).toBe(8 * chunk.length)
   }, 90_000)
 
+
   it('bounds a flood of zero-byte log lines through the per-entry separator charge', async () => {
     // Blank print() lines carry zero content bytes; without the +1 separator
     // charge they would bypass maxLogBytes entirely and grow the retained