fix(e2e): instrument sim RF path; graceful shutdown; richer failure logs

Both e2e directions time out: nothing is delivered between nodes although
the adapter connects fine and bridging code is equivalent to meshtastic's own
firmware_harness. Before concluding, instrument the pinned meshtasticator:
- on_receive now prints every observed packet (topic keys) to sim.log,
- a [sim-text] listener prints any text packet any sim interface sees,
- cleanup sends 'exit' through the cmdloop (graceful, no EOF-spam flood that
  was drowning the log tail),
- workflow failure step prints 400 sim-log lines + the node logs dump.

.gitea/workflows/meshtasticator-e2e.yaml

@@ -84,7 +84,9 @@ jobs:
       - name: Print simulator log (on failure)
         if: failure()
         run: |
-          echo "===== meshtasticator-sim.log ====="
-          tail -n 200 meshtasticator-sim.log 2>/dev/null || true
+          echo "===== meshtasticator-sim.log (tail) ====="
+          tail -n 400 meshtasticator-sim.log 2>/dev/null || true
+          echo "===== meshtasticator-nodes.log (if any) ====="
+          tail -n 200 meshtasticator-nodes.log 2>/dev/null || true
           echo "===== docker ps ====="
           docker ps -a 2>/dev/null || true