fix(python): avoid a runtime typing_extensions dependency

[nachiketb-nvidia]

What

• Load typing_extensions.Self only while type checking.
• Make the existing slim-install and release-wheel smoke checks import the native Server entry point.

Why

A clean default install has no typing_extensions runtime dependency, but switchyard_rust.server imported it unconditionally. This made the supported server entry point fail before the native module could load.

Validation

• Clean isolated install and Server import on Python 3.10 with typing_extensions absent.
• Clean isolated install and Server import on Python 3.14 with typing_extensions absent.
• uv run ruff check switchyard_rust/server.py
• uv run mypy switchyard_rust/server.py
• Repository pre-commit hooks.

Fixes SWITCH-1425.

Summary by CodeRabbit

• Bug Fixes
  • Improved runtime loading for the server component by avoiding an unnecessary typing-related dependency during execution.
• Tests
  • Expanded installation and wheel smoke tests to verify that the server component can be imported successfully across supported Python versions.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Configuration used: Path: .coderabbit.yaml

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Plan: Enterprise

Run ID: 62a6cc3c-2795-4972-988f-55da166817fb

📥 Commits

Reviewing files that changed from the base of the PR and between 3807ff0 and 28c3c39.

📒 Files selected for processing (3)

• .github/workflows/ci.yml
• .github/workflows/publish.yml
• switchyard_rust/server.py

Included review availability: Your plan provides up to 12 included reviews per hour; 11 remain after this review.

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Walkthrough

The change removes the runtime typing_extensions import from server.py. Slim-install and wheel smoke tests now import and print switchyard_rust.server.Server for Python 3.10 and 3.14.

Changes

Server import validation

Layer / File(s)	Summary
Runtime import handling switchyard_rust/server.py	load_native is imported unconditionally. Self is imported from typing_extensions only during type checking.
Smoke-test Server checks .github/workflows/ci.yml, .github/workflows/publish.yml	Slim-install and wheel smoke tests import and print switchyard_rust.server.Server for Python 3.10 and 3.14.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~5 minutes

Merge Risk: ⚪ Minimal · up to 28c3c

The supported Server entry point avoids the runtime typing dependency and is covered by matching slim-install and wheel smoke checks.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely describes the main change: removing the runtime dependency on typing_extensions from the Python server import path.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 1…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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_{A rabbit checks the server door
Imports hop cleanly as before
Slim wheels print the class with pride
Type hints wait on the checking side
Four small tests now spring outside}

_{Comment @coderabbitai help to get the list of available commands.}

[ayushag-nv]

Lgtm