chore(main): release 1.91.0

[release-please]

🤖 I have created a release beep boop

1.91.0

1.91.0 (2026-09-04)

⚠ BREAKING CHANGES

• datalabeling: remove java-datalabeling library (#14189)
• datacatalog: remove java-datacatalog library (#14178)

Features

• apptopology: onboard a new library (#14204) (f871a07)
• bigtable: Option to disable direct access fallback (#14193) (5b6a974)
• datacatalog: remove java-datacatalog library (#14178) (2910f63)
• datalabeling: remove java-datalabeling library (#14189) (334d35a), refs #14176
• gax: add getSingleHeader to HttpHeadersUtils (#14137) (f114422)
• gax: add ResumableUploadClient.startUpload() and supporting types (#14138) (d7e2be2)
• gax: add ResumableUploadResponseParser (#14135) (e1a0b17)
• gax: allow non-JSON HttpContent and absolute request URLs in HttpRequestRunnable (#14134) (ac4a49a)
• gax: implement queryStatusCallable for resumable uploads (#14155) (67719c0)
• gax: implement startUploadCallable for resumable uploads (#14139) (4e65b6c)
• gax: implement uploadChunkCallable for resumable uploads (#14140) (1c643de)
• google/shopping/merchant/loyaltycustomers/v1: onboard new library (#14257) (590a51c)
• grpc-gcp: drain scaled-down channels (#14216) (bbbd18c)
• grpc-gcp: move scale-up to background worker (#14206) (41f0a2e)
• grpc-gcp: penalize retryable channel errors (#14219) (829872e)
• grpc-gcp: prime scaled channels before publish (#14232) (dd75645)
• spanner: add client-level CallContextConfigurator to SpannerOptions (#14256) (eef74d2)
• spanner: prime scaled-up dynamic channel pool channels with SELECT 1 (#14254) (4d26645)

Bug Fixes

• auth: refine JSpecify nullability annotations for external account credentials (#14164) (385e1f2)
• bigtable: truncate client generated timestamps on the emulator c… (#14234) (94e680f)
• gax: propagate structured LRO error details to ApiException (#14022) (865a15b)
• grpc-gcp: correct channel lifecycle bookkeeping (#14196) (3df32ba)
• grpc-gcp: prevent hot-channel skew (#14198) (07a7505)
• java-sql: temp fix for lint and skip generate (#14005) (b6f73db)
• spanner: prioritize leader replica for read-write transactions in location-aware routing (#14195) (6383f81)
• spanner: route ExecuteBatchDml through transaction affinity endpoint (#14192) (5e9e3cd)
• storage: resolve GraalVM Native Image test failure for java-storage (#14226) (93e0920)

Performance Improvements

• bigquery-jdbc: eliminate sync getJob RPC call (#14197) (ccf12b0)
• ci: replace mvn help:evaluate with native bash and sed extraction (#14218) (744a522)

Dependencies

• Upgrade grpc-java to 1.83.0 (#13967) (0cdc695)

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This PR was generated with Release Please. See documentation.

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[lqiu96]

PR was merged. re-creating