Python: Bump Python package versions for a release. (#5432)

* Bump Python version for a release.

* Revert lockstep bumps on unchanged connectors

Per PR review: only connectors that changed (or whose published metadata
changed) should get new versions. Keeps released tier at 1.1.1, a2a/ag-ui
at 1.0.0b260422, foundry-hosting at 1.0.0a260422; reverts the 19 unchanged
betas and 2 unchanged alphas to 1.0.0b260421/1.0.0a260421. Reverts all 26
non-core agent-framework-core floors to >=1.1.0,<2 since no connector
actually depends on a 1.1.1 API or bug fix.

* Restore lockstep prerelease bumps and raise core floors to >=1.1.1

Reverses the lean-revert: all beta packages stamped 1.0.0b260423 and alpha
packages stamped 1.0.0a260423 (Asia date, matching release cut time). All
26 non-core packages raise agent-framework-core lower bound from >=1.1.0,<2
to >=1.1.1,<2 to signal the validated cohort for this release. CHANGELOG
date updated to 2026-04-23.

python/packages/github_copilot/pyproject.toml

@@ -4,7 +4,7 @@ description = "GitHub Copilot integration for Microsoft Agent Framework."
 authors = [{ name = "Microsoft", email = "af-support@microsoft.com"}]
 readme = "README.md"
 requires-python = ">=3.10"
-version = "1.0.0b260421"
+version = "1.0.0b260423"
 license-files = ["LICENSE"]
 urls.homepage = "https://aka.ms/agent-framework"
 urls.source = "https://github.com/microsoft/agent-framework/tree/main/python"
@@ -23,7 +23,7 @@ classifiers = [
   "Typing :: Typed",
 ]
 dependencies = [
-    "agent-framework-core>=1.1.0,<2",
+    "agent-framework-core>=1.1.1,<2",
     "github-copilot-sdk>=0.2.1,<=0.2.1; python_version >= '3.11'",
 ]