chore(telemetry): Log `FIREBASE_STUDIO` when using Gemini CLI within Firebase Studio (#5790)

packages/core/src/telemetry/clearcut-logger/clearcut-logger.ts

@@ -51,6 +51,25 @@ export interface LogResponse {
   nextRequestWaitMs?: number;
 }
 
+/**
+ * Determine the surface that the user is currently using.  Surface is effectively the
+ * distribution channel in which the user is using Gemini CLI.  Gemini CLI comes bundled
+ * w/ Firebase Studio and Cloud Shell.  Users that manually download themselves will
+ * likely be "SURFACE_NOT_SET".
+ *
+ * This is computed based upon a series of environment variables these distribution
+ * methods might have in their runtimes.
+ */
+function determineSurface(): string {
+  if (process.env.CLOUD_SHELL === 'true') {
+    return 'CLOUD_SHELL';
+  } else if (process.env.MONOSPACE_ENV === 'true') {
+    return 'FIREBASE_STUDIO';
+  } else {
+    return process.env.SURFACE || 'SURFACE_NOT_SET';
+  }
+}
+
 // Singleton class for batch posting log events to Clearcut. When a new event comes in, the elapsed time
 // is checked and events are flushed to Clearcut if at least a minute has passed since the last flush.
 export class ClearcutLogger {
@@ -237,10 +256,7 @@ export class ClearcutLogger {
   }
 
   logStartSessionEvent(event: StartSessionEvent): void {
-    const surface =
+    const surface = determineSurface();
-      process.env.CLOUD_SHELL === 'true'
-        ? 'CLOUD_SHELL'
-        : process.env.SURFACE || 'SURFACE_NOT_SET';
 
     const data = [
       {