fix(release): improve release process and docs

[droctothorpe]

Description of your changes:
This PR encapsulates a bunch of fixes that @zazulam and I had to implement in order to release 2.16.0. It also includes various documentation updates.

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[google-oss-prow]

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[droctothorpe]

We put TODOs here @HumairAK. We can implement them in follow up PRs. I need to not look at this documentation again for a little while. #brainbleach

[Copilot]

Pull request overview

This PR improves the KFP release process and documentation based on lessons learned from releasing version 2.16.0. It addresses cross-platform compatibility issues, fixes dependency installation order, updates documentation tooling, and significantly enhances the RELEASE.md guide with more detailed instructions and troubleshooting information.

Changes:

• Added portable sedi() function for macOS/Linux sed compatibility in release scripts
• Fixed test dependency installation order in CI to install kfp-server-api before test dependencies
• Updated Sphinx and related documentation dependencies to newer versions (Sphinx 5.0.2 → 7.2.6)
• Enhanced proto generation script with better error handling and distutils.spawn deprecation fix
• Improved version extraction in release scripts to avoid import-time dependency issues
• Extensively updated RELEASE.md with clearer instructions, new sections, and practical improvement suggestions

Reviewed changes

Copilot reviewed 10 out of 10 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
test/release/release.sh	Added portable sedi() function for cross-platform sed support and automated ConfigMap version updates
sdk/python/pre-release-requirements-update.sh	Added wheel building steps before pip-compile to ensure local dependencies are available
kubernetes_platform/python/pre-release-requirements-update.sh	Added wheel building steps for all dependencies before pip-compile
kubernetes_platform/python/generate_proto.py	Fixed distutils.spawn deprecation, improved path handling, added error checking for protoc generation
kubernetes_platform/python/docs/requirements.txt	Updated Sphinx and related packages to newer versions
docs/sdk/requirements.txt	Updated Sphinx and related packages to newer versions
kubernetes_platform/python/create_release_branch.sh	Changed version extraction to use grep/sed instead of Python import to avoid dependency issues
RELEASE.md	Comprehensive documentation improvements including better structure, clearer instructions, and opportunities for future improvements
.readthedocs.yml	Updated Python version from 3.9 to 3.11
.github/workflows/kfp-sdk-client-tests.yml	Fixed dependency installation order to install kfp-server-api before test dependencies

Comments suppressed due to low confidence (6)

RELEASE.md:160

• There appears to be stray text "333" at the end of this line. This should be removed as it looks like accidental content that was inserted during editing.

This script updates the version values for various manifests, and generated code.333

RELEASE.md:365

• There's a typo "t Use" at the beginning of this line - the "t" should be removed. The line should start with "Use this template..."

t Use this template for public releases and replace the `$VERSION` with real values.

kubernetes_platform/python/pre-release-requirements-update.sh:14

• The variable $GIT_ROOT should be quoted in the cd commands to handle paths with spaces properly. Change to cd "$GIT_ROOT/api/v2alpha1/python" on all lines where cd is used with $GIT_ROOT. This is a best practice for shell scripting to prevent word splitting and globbing issues.

cd $GIT_ROOT/api/v2alpha1/python
python setup.py bdist_wheel

cd $GIT_ROOT/backend/api/v2beta1/python_http_client
python setup.py bdist_wheel

cd $GIT_ROOT/sdk/python
python setup.py bdist_wheel

cd $GIT_ROOT/kubernetes_platform/python

.readthedocs.yml:11

• The Python version was updated to 3.11 in the root .readthedocs.yml, but kubernetes_platform/python/docs/.readthedocs.yml still uses Python 3.9. For consistency and to ensure both documentation builds use the same Python version, consider updating the kubernetes_platform readthedocs config to also use Python 3.11. This would align the documentation builds across both SDK and kubernetes platform packages.

    python: "3.11"

sdk/python/pre-release-requirements-update.sh:11

• The variable $GIT_ROOT should be quoted in the cd commands to handle paths with spaces properly. Change to cd "$GIT_ROOT/api/v2alpha1/python" on all lines where cd is used with $GIT_ROOT. This is a best practice for shell scripting to prevent word splitting and globbing issues.

cd $GIT_ROOT/api/v2alpha1/python
python setup.py bdist_wheel

cd $GIT_ROOT/backend/api/v2beta1/python_http_client
python setup.py bdist_wheel

cd $GIT_ROOT/sdk/python

RELEASE.md:402

• The reference to "Claude" at line 402 is informal and may not be appropriate for official release documentation. Consider either removing this sentence entirely (since the command names are self-explanatory) or replacing it with a more formal reference, such as "For details about what make release-in-place does, see [link to documentation]" or simply removing the parenthetical comment altogether.

Run the following code. If you're curious about what `make release-in-place` does, here's some context from Claude.

[droctothorpe]

/retest

[droctothorpe]

/retest