Fixes an issue where reusing recently created Cloud Functions during
Remote Function creation would sometimes result in an empty endpoint
(`endpoint=""`).

When a Cloud Function has been recently provisioned, its endpoint URI
(`response.service_config.uri`) may occasionally be returned as an empty
string if URL propagation is still pending. The remote function
decorator previously only checked for `None`, proceeding to create the
BigQuery Remote Function with `OPTIONS(endpoint='')`, which leads to
validation failures when queries invoke the function.

This PR changes the check to `if not cf_endpoint:` to handle both `None`
and empty strings. If the endpoint is empty, it will route to
`create_cloud_function`, which catches the `AlreadyExists` exception and
safely retries/waits for the endpoint URI propagation to complete.

Fixes #<525124882> 🦕

🤖 I have created a release *beep* *boop*
---


##
[2.44.0](bigframes-v2.43.0...bigframes-v2.44.0)
(2026-06-25)


### Features

* add date functions to `bigframes.bigquery` module
([#17514](#17514))
([e5d2e35](e5d2e35))
* **bigframes:** add AI TVFs to the pandas bq accessor
([#17402](#17402))
([ee74e31](ee74e31))
* Experimental transpilation of unannotated python callables
([#17419](#17419))
([ea9aad9](ea9aad9))
* support gemini-3.x models in loader and update default model to
gemini-3.5-flash
([#17557](#17557))
([3619b29](3619b29))
* support interactive execution of deferred DataFrames in TableWidget
([#17486](#17486))
([421eebd](421eebd))


### Bug Fixes

* avoid invalid CAST(NULL AS NULL) in SQLGlot compiler
([#17487](#17487))
([3b79caa](3b79caa))
* **bigframes:** world-readable temp zip in create_cloud_function
([#17522](#17522))
([e726878](e726878))
* bump @angular/common, @angular/forms, @angular/platform-browser and
@angular/router in
/packages/bigframes/bigframes/display/table_widget_angular
([#17525](#17525))
([2f893b1](2f893b1))
* bump langsmith from 0.8.0 to 0.8.18 in /packages/bigframes
([#17518](#17518))
([f23063f](f23063f))
* bump msgpack from 1.1.1 to 1.2.1 in /packages/bigframes
([#17520](#17520))
([36b5b7e](36b5b7e))
* bump undici and @angular/build in
/packages/bigframes/bigframes/display/table_widget_angular
([#17519](#17519))
([6fc45e3](6fc45e3))
* handle empty endpoints during cloud function reuse
([#17501](#17501))
([4f5593a](4f5593a))


### Documentation

* ensure that PlotAccessor is included in the API reference
([#17513](#17513))
([6febabf](6febabf))

---
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Please](https://github.com/googleapis/release-please). See
[documentation](https://github.com/googleapis/release-please#release-please).

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