What and why?

Adds telemetry-flow verification to the Azure App Service (Linux + Windows) e2e suites so they assert that telemetry actually reaches Datadog under a run-specific identity -- not just that instrumentation config was applied. Linux asserts spans and logs; Windows asserts spans (Windows App Service does not support Datadog log collection).

Stacked on #2364, and depends on #2369 (shared telemetry checker).

How?

• Instrument with explicit service / env / version and a one_e2e_run_id extra tag so the checker asserts identity, not mere existence.
• Instrument with the same Datadog API key the telemetry checker queries with (DATADOG_API_KEY), so the spans/logs land in the org the assertions read from.
• Linux: pass --instance-logging so the sidecar forwards the app's stdout logs, not just traces.
• Windows: deploy the app via az webapp deploy (zipdeploy) with SCM_DO_BUILD_DURING_DEPLOYMENT, so Oryx generates the iisnode web.config IIS needs to route requests to the Node app. (Mounting the package read-only via WEBSITE_RUN_FROM_PACKAGE skips that build, so the app 403s.) Auth uses the az-login AAD token; the SCM site can return a 502 while cold, so the deploy retries. (Requires the CI service principal to have Website Contributor on the e2e resource group for the SCM deploy.)
• Drive sustained traffic via the shared triggerTraffic helper so the trace/log pipeline has time to warm up after a cold start before we assert telemetry.
• telemetry flows asserts identity (service + env + version + run-id tag) via the shared telemetry checker -- spans + logs on Linux, spans only on Windows.
• Add an idempotency test: re-instrument is a no-op and config stays singular.
• Add the shared traffic.ts and telemetry checker to the AAS CI path filter.

Test plan

• AAS Linux + Windows e2e run in the End-to-end test the package GitHub Actions job (gated by the aas path filter + Azure OIDC); all three Node matrix versions green with live spans (Linux: spans + logs) flowing to Datadog.

Review checklist

• Feature or bugfix MUST have appropriate tests (unit, integration)