fix(gcs): trim whitespace from bucket_override input

Address review feedback: the manual bucket override is free-form text and
users often copy-paste bucket names, which can introduce leading/trailing
whitespace (spaces, newlines) and cause hard-to-debug GCS API errors (400/404).

Trim bucket_override before use; a whitespace-only value trims to "" and falls
back to the dropdown bucket. Tighten the test helper's bucket assertion to an
exact match (calledWith) so the trimming is actually verified, and add tests
for the trimmed and whitespace-only-fallback cases.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: vklm2002

src/actions/google/gcs/google_cloud_storage.ts

@@ -45,7 +45,7 @@ export class GoogleCloudStorageAction extends Hub.Action {
     // The manual override takes precedence over the bucket selected from the dropdown. This allows
     // writing to a bucket in another project (e.g. a partner bucket) where the service account only
     // has object-level access (storage.objects.create) and cannot list buckets at the project level.
-    const bucket = request.formParams.bucket_override || request.formParams.bucket
+    const bucket = request.formParams.bucket_override?.trim() || request.formParams.bucket
 
     if (!bucket) {
       const error: Error = errorWith(

src/actions/google/gcs/test_google_cloud_storage.ts

@@ -69,7 +69,9 @@ function expectGoogleCloudStorageMatch(request: Hub.ActionRequest,
   // so stubbing it again would throw. Such callers pass stubNow = false.
   const stubDate = stubNow ? sinon.stub(Date, "now").callsFake(() => 1234) : undefined
   return chai.expect(action.validateAndExecute(request)).to.be.fulfilled.then(() => {
-    chai.expect(bucketSpy).to.have.been.calledWithMatch(bucketMatch)
+    // Exact match (not calledWithMatch, which does substring matching for strings) so that
+    // whitespace-trimming assertions on the bucket name are meaningful.
+    chai.expect(bucketSpy).to.have.been.calledWith(bucketMatch)
     chai.expect(fileSpy).to.have.been.calledWithMatch(fileMatch)
     stubClient.restore()
     stubSuggestedFilename.restore()
@@ -430,6 +432,46 @@ describe(`${action.constructor.name} unit tests`, () => {
         "mywackyfilename",
         Buffer.from("1,2,3,4", "utf8"))
     })
+
+    it("trims whitespace from the bucket_override value", () => {
+      const request = new Hub.ActionRequest()
+      request.type = Hub.ActionType.Dashboard
+      request.params = {
+        client_email: "myemail",
+        private_key: "mykey",
+        project_id: "myproject",
+      }
+      request.formParams = {
+        bucket: "listedbucket",
+        bucket_override: "  partner-bucket\n",
+        filename: "mywackyfilename",
+      }
+      request.attachment = {dataBuffer: Buffer.from("1,2,3,4", "utf8")}
+      return expectGoogleCloudStorageMatch(request,
+        "partner-bucket",
+        "mywackyfilename",
+        Buffer.from("1,2,3,4", "utf8"))
+    })
+
+    it("falls back to the dropdown bucket when bucket_override is only whitespace", () => {
+      const request = new Hub.ActionRequest()
+      request.type = Hub.ActionType.Dashboard
+      request.params = {
+        client_email: "myemail",
+        private_key: "mykey",
+        project_id: "myproject",
+      }
+      request.formParams = {
+        bucket: "listedbucket",
+        bucket_override: "   ",
+        filename: "mywackyfilename",
+      }
+      request.attachment = {dataBuffer: Buffer.from("1,2,3,4", "utf8")}
+      return expectGoogleCloudStorageMatch(request,
+        "listedbucket",
+        "mywackyfilename",
+        Buffer.from("1,2,3,4", "utf8"))
+    })
   })
 
   describe("form", () => {