Co-authored-by: release-please[bot] <55107282+release-please[bot]@users.noreply.github.com>

This PR adds `biome.json` to enforce consistent 2-space indentation and
single quotes for JavaScript and CSS files. This aligns with project
style guides, automates formatting via pre-commit hooks, and prevents
manual style changes from being overwritten.

Currently, our Biome setup relies on default settings, which violates
Google coding style guidelines. Specifically:
* **Quotation Marks:** Biome's defaults do not enforce single quotes for
JavaScript (as per `js_style.txt`: `screen/8NaEr3SswN6qx6D`) and CSS
property values (as per `css_style.txt`: `screen/9KCh8ZVQ4ByPeDR`).
* **Indentation:** Biome's defaults do not consistently enforce 2 spaces
for indentation across HTML (`screen/97ZZstQc4iH4Dsb`) and JavaScript
(`screen/3crxm5peLvRE2kj`) files.

This configuration explicitly sets these rules to ensure full
compliance.

**Benefits:**
*   Consistent and readable JS/CSS code.
*   Automated style enforcement.
*   Reduced developer friction.

**To Test:**
Make a style-violating change in a `.js` or `.css` file and attempt to
commit. Biome should automatically reformat it.

Fixes #<issue_number_goes_here> 🦕

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:e7cc6823efb073a8a26e7cefdd869f12ec228abfbd2a44aa9a7eacc284023677
<details><summary>bigframes: 2.33.0</summary>

##
[2.33.0](googleapis/python-bigquery-dataframes@v2.32.0...v2.33.0)
(2026-01-22)

### Features

* add bigquery.ml.transform function (#2394)
([1f9ee373](googleapis/python-bigquery-dataframes@1f9ee373))

* Add dark mode to anywidget mode (#2365)
([2763b41d](googleapis/python-bigquery-dataframes@2763b41d))

* Add max_columns control for anywidget mode (#2374)
([34b5975f](googleapis/python-bigquery-dataframes@34b5975f))

* Configure Biome for Consistent Code Style (#2364)
([81e27b3d](googleapis/python-bigquery-dataframes@81e27b3d))

* Add BigQuery ObjectRef functions to `bigframes.bigquery.obj` (#2380)
([9c3bbc36](googleapis/python-bigquery-dataframes@9c3bbc36))

* Stabilize interactive table height to prevent notebook layout shifts
(#2378)
([a634e976](googleapis/python-bigquery-dataframes@a634e976))

### Bug Fixes

* implement retry logic for cloud function endpoint fetching (#2369)
([0f593c27](googleapis/python-bigquery-dataframes@0f593c27))

* Throw if write api commit op has stream_errors (#2385)
([7abfef05](googleapis/python-bigquery-dataframes@7abfef05))

### Performance Improvements

* Avoid requery for some result downsample methods (#2219)
([95763ff2](googleapis/python-bigquery-dataframes@95763ff2))

</details>