[Step7750]

Summary

• Share a single in-flight trade status ping between the alarm, service worker wake-up, and page bridge triggers
• Run one notary proof at a time
• Wait for the offscreen document to be ready before sending it requests, and reset creation state if it fails
• Use wss:// for the notary session WebSocket
• Skip background notary proving on Chrome versions without the offscreen WORKERS reason
• Add a test for the shared ping run

Ref CSF-2167

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Note

Medium Risk
Changes concurrency and offscreen/notary session wiring for trade status and TLSN proofs; incorrect deduplication or readiness timing could miss updates or break proving on some browsers.

Overview
Prevents duplicate background work when alarms, service worker wake-ups, or other triggers overlap.

pingTradeStatus now deduplicates concurrent calls without a Steam ID into a single in-flight run, while calls that pass expectedSteamID (page bridge) still run independently so user-specific fetches are not skipped.

Notary proving is limited to one concurrent proof (down from two) because the offscreen document can close after a proof and abort other in-flight work. Background notary is disabled on Firefox and on Chrome builds missing chrome.offscreen.Reason.WORKERS.

Offscreen lifecycle: openOffscreenDocument uses a shared creation promise so parallel openers always wait for the offscreen_ready message before proceeding. The notary session client builds WebSocket URLs via toWebSocketUrl (wss://) for older Chrome that rejects http(s) in WebSocket.

Adds a unit test asserting shared vs independent pingTradeStatus behavior.

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