refactor(telemetry): drop dead live-collector smoke and the compact/end severity probe

tests/otel.e2e.ts self-skipped on $DSH_OTLP_E2E_ENDPOINT, which nothing in
the repo sets — it never ran; the mock-collector wire spec and the keyless
Loader-composition e2e already cover the pipeline both ways.

The severityOf compact/end probe parsed another package's merged event
shape by string comparison — an untyped cross-package contract that breaks
silently — and its only consumer was the test's own stand-in declaration.
Unknown event types now uniformly fall through as info; outcome semantics
stay with the owning package.

docs/cordis-catalog/services.md

@@ -1554,7 +1554,7 @@ flush?(): void
 abstract shutdown(): Promise<void>
 ```
 
-Source: [`packages/telemetry/session-telemetry/src/index.ts:124`](../../packages/telemetry/session-telemetry/src/index.ts)
+Source: [`packages/telemetry/session-telemetry/src/index.ts:125`](../../packages/telemetry/session-telemetry/src/index.ts)
 
 ## `ctx.tokenMeter` — `TokenMeterService`