observability(events-ws): log per-PP event delivery + drop reasons on the listener

[AquiGorka]

Working from: /Users/theahaco/repos/pm-theahaco/prompts/force-evidence-based-testnet-validation-1-prompt.md

What this addresses

Per-PP events emitted by verifier.process.handleVerificationSuccess (verifier.bundle_completed, bundle.deposit_completed, bundle.withdraw_completed) inconsistently fail to reach the harness on deployed testnet. Failure window log slice for the most recent sweep:

$ jq -cs --arg start "2026-06-09T16:33:25Z" --arg end "2026-06-09T16:37:43Z" \
    'map(select(.timestamp >= $start and .timestamp <= $end)) | length' \
    provider-platform-logs.json
0

Zero log lines. The handler's existing events WS opened / events WS closed / events WS error (ws-handler.ts:156, 161, 165) also did not fire — so the per-PP WS lifecycle for the failing PP cannot be reconstructed from logs at all.

The listener gap

ws-handler.ts:140-149 (pre-fix):

const listener = (event: ProviderEvent) => {
  if (event.scope.ppPublicKey !== boundPpPublicKey) return;
  if (socket.readyState !== WebSocket.OPEN) return;
  try {
    socket.send(JSON.stringify(event));
  } catch (error) {
    log.debug("kind", event.kind);
    log.error(error, "failed to send event over WS");
  }
};

The listener has no log for the happy path (event matched + sent) and no log for the early-return on readyState !== OPEN. The only listener log fires on socket.send throwing.

Change

Add .event() + .debug() calls for both branches inside the listener. No behavioral change. No new dependencies. No config touched.

     const listener = (event: ProviderEvent) => {
       if (event.scope.ppPublicKey !== boundPpPublicKey) return;
-      if (socket.readyState !== WebSocket.OPEN) return;
+      if (socket.readyState !== WebSocket.OPEN) {
+        log.debug("kind", event.kind);
+        log.debug("readyState", socket.readyState);
+        log.event("event dropped: WS not OPEN");
+        return;
+      }
       try {
         socket.send(JSON.stringify(event));
+        log.debug("kind", event.kind);
+        log.event("event sent to WS");
       } catch (error) {
         log.debug("kind", event.kind);
         log.error(error, "failed to send event over WS");
       }
     };

Failure output that motivates this (verbatim, sweep.log)

[events-capture] FAIL — script testnet-main — run testnet-main-2026-06-09T16-37-42-906Z
[events-capture]   perPp:GAFBCHCG5TOPHUPT6DY3S26BJ5X5DYHCA2OVFPDSU7VSDE3ZOMO2ZUGW: FAIL — expected 12, captured 9
[events-capture]   network: PASS (5/5)
    [0] OK   kind="channel.provider_added"
    [1] OK   kind="mempool.bundle_added"
    [2] OK   kind="executor.transaction_submitted"
    [3] OK   kind="verifier.bundle_completed"
    [4] OK   kind="bundle.deposit_completed"
    [5] OK   kind="mempool.bundle_added"
    [6] OK   kind="executor.transaction_submitted"
    [7] DIFF kind mismatch: expected "verifier.bundle_completed" got "mempool.bundle_added"
    [8] DIFF kind mismatch: expected "mempool.bundle_added" got "executor.transaction_submitted"
    [9] MISS expected "executor.transaction_submitted" not received
    [10] MISS expected "verifier.bundle_completed" not received
    [11] MISS expected "bundle.withdraw_completed" not received

Test plan

• deno fmt, deno lint, deno check src/http/v1/events/ws-handler.ts clean
• deno test src/http/v1/events/ — 1/1 (existing WS-stays-OPEN test unchanged and still passing)
• deno.json: 0.7.6 → 0.7.7 (auto-tag precondition)
• After merge + testnet deploy: re-run a sweep; quote the new listener log lines from flyctl logs for the failure window to confirm whether missing per-PP events are dropped at the listener-OPEN gate or never reach the listener.