PR created by the Librarian CLI to initialize a release. Merging this PR
will auto trigger a release.

Librarian Version: v0.7.0
Language Image:
us-central1-docker.pkg.dev/cloud-sdk-librarian-prod/images-prod/python-librarian-generator@sha256:160860d189ff1c2f7515638478823712fa5b243e27ccc33a2728669fa1e2ed0c
<details><summary>bigframes: 2.39.0</summary>

##
[2.39.0](v2.38.0...v2.39.0)
(2026-03-31)

### Features

* add `df.bigquery.ai.forecast` method to pandas dataframe accessor
(#2518)
([1126cec](1126cec9))

* support full round-trip persistence for multimodal reference cols
(#2511)
([494a0a1](494a0a11))

* expose DataFrame.bigquery in both pandas and bigframes DataFrames
(#2533)
([69fe317](69fe3176))

### Bug Fixes

* to_gbq may swap data columns when replace table (#2532)
([17ecc65](17ecc65e))

* handle aggregate operations on empty selections (#2510)
([34fb5da](34fb5daa))

* Localize BigQuery log suppression for gbq.py (#2541)
([af49ca2](af49ca29))

* Respect remote function config changes even if logic unchanged (#2512)
([b952428](b9524284))

* support melting empty DataFrames without crashing (#2509)
([e8c4603](e8c46032))

### Performance Improvements

* Make executor data uploads async internally (#2529)
([96597f0](96597f0b))

### Documentation

* gemini retouch of the index page for seo (#2514)
([2e5311e](2e5311e2))

* Rename Blob column references to ObjectRef column (#2535)
([44e0ffd](44e0ffd9))

</details>