ai: apply changes for #506 (2 review threads)

Addresses:
  - #3876121332 at tests/unit/DBSQLClient.test.ts:966
  - #3876121337 at lib/kernel/KernelAuth.ts:685

Signed-off-by: peco-engineer-bot[bot] <peco-engineer-bot[bot]@users.noreply.github.com>

Author: peco-engineer-bot[bot]

lib/kernel/KernelAuth.ts

@@ -701,10 +701,15 @@ export function buildKernelTelemetryOptions(
   if (Number.isFinite(config.telemetryCloseTimeoutMs)) {
     telemetry.telemetryCloseFlushTimeoutMs = config.telemetryCloseTimeoutMs;
   }
-  if (Number.isFinite(config.telemetryCircuitBreakerThreshold)) {
+  // The breaker is forced on above, and the napi contract requires threshold/timeout
+  // to be strictly positive when it is enabled. A caller-supplied `0` (or negative)
+  // would otherwise be forwarded verbatim and surface as a hard kernel `openSession`
+  // rejection, so treat any non-positive value as a misconfiguration and fall back to
+  // the kernel defaults (5 / 60000) instead.
+  if (Number.isFinite(config.telemetryCircuitBreakerThreshold) && config.telemetryCircuitBreakerThreshold! > 0) {
     telemetry.telemetryCircuitBreakerThreshold = config.telemetryCircuitBreakerThreshold;
   }
-  if (Number.isFinite(config.telemetryCircuitBreakerTimeout)) {
+  if (Number.isFinite(config.telemetryCircuitBreakerTimeout) && config.telemetryCircuitBreakerTimeout! > 0) {
     telemetry.telemetryCircuitBreakerTimeoutMs = config.telemetryCircuitBreakerTimeout;
   }
 

tests/unit/DBSQLClient.test.ts

@@ -5,6 +5,7 @@ import DBSQLClient, { ThriftLibrary } from '../../lib/DBSQLClient';
 import DBSQLSession from '../../lib/DBSQLSession';
 import ThriftBackend from '../../lib/thrift-backend/ThriftBackend';
 import KernelBackend from '../../lib/kernel/KernelBackend';
+import * as KernelNativeLoader from '../../lib/kernel/KernelNativeLoader';
 
 import PlainHttpAuthentication from '../../lib/connection/auth/PlainHttpAuthentication';
 import DatabricksOAuth from '../../lib/connection/auth/DatabricksOAuth';
@@ -963,6 +964,13 @@ describe('DBSQLClient telemetry paths', () => {
       delete process.env.DATABRICKS_TELEMETRY_DISABLED;
       const client = new DBSQLClient();
       const initStub = sinon.stub(client as any, 'initializeTelemetry').resolves();
+      // DBSQLClient constructs `new KernelBackend({ context: this })` without
+      // injecting a `nativeBinding`, so the KernelBackend constructor calls
+      // `getKernelNative()`, which throws where the native `.node` artifact
+      // isn't built (e.g. CI). Stub the loader so construction succeeds and the
+      // assertion below tests the `!useKernel` telemetry gate rather than the
+      // presence of a built kernel artifact.
+      sinon.stub(KernelNativeLoader, 'getKernelNative').returns({} as any);
       sinon.stub(KernelBackend.prototype, 'connect').resolves();
       sinon.stub(KernelBackend.prototype, 'close').resolves();