P1: compiled runtime logging lifecycle for OpenTelemetry and Loki

[07prajwal2000]

Problem

The compiled request path creates logging infrastructure on every request. setupContextVars mutates shared integration configuration with route/project IDs, OpenTelemetryLogs creates a provider/exporter and force-flushes each log, and Loki creates a transport per request. Providers, exporters, timers, and sockets are never shut down. Concurrent requests can race and mislabel logs.

Scope

• Cache logger, OpenTelemetry provider/exporter, and Loki transport per integration in the execution thread.
• Treat integration configuration as immutable; attach project and route identifiers as per-log attributes.
• Batch exports; flush and close all resources during worker shutdown.
• On integration configuration change, atomically replace the cached logging resources and close the retired provider after it drains.
• Define the boundary with Admin telemetry worker: trace transport, JetStream stream and span consumer #195 so compiled-worker logs can use the existing telemetry path without creating an exporter for each request.
• Add lifecycle and concurrency tests for labeling, replacement, batching, and shutdown.

Acceptance

• Concurrent routes cannot cross-label logs.
• A stable integration creates bounded providers/transports under sustained load.
• Log exports batch normally and all resources flush/close on shutdown.
• Replacing integration config eventually closes the old provider and uses the new credentials.

Split from #192. Part of #194.