feat: add web console usage telemetry

[emrberk]

Adds anonymous, opt-in usage telemetry to the web console. Events are stored locally in IndexedDB and flushed to the server in batches.

Telemetry infrastructure (ConsoleEventTracker module)

• trackEvent(name, payload?): fire-and-forget entry point; writes to IndexedDB via Dexie (db.ts)
• sendPipeline.ts: background flush loop that runs every 5 s when there are pending events
• Calls console-events-config to get the server-side cursor (lastUpdated), then POSTs only newer events via add-console-events
• Exponential back-off (base 1 s, up to 2^9 s) with independent retry counters for the check and send phases
  • MAX_BATCH_SIZE = 1 000 events per POST; successfully sent entries are deleted from IndexedDB immediately
  • On startup, trimToMaxRows(10 000) evicts the oldest events to bound local storage

[jerrinot]

when someone click at the "(AI) Configure" button then we don't collect it as an event. maybe we should? "people who read about the AI assistance but decided NOT to set it up"?

[jerrinot]

the PR description says:

Adds anonymous, opt-in usage telemetry to the web console.

is it actually opt-in? the console did not ask me anything yet it's sending events.