Align published Python compatibility guidance with worker protocol 1.19

[rmcdaniel]

Problem

Python SDK 2.0.0-rc.40 declares worker protocol 1.19 and rejects servers whose worker-protocol minor is lower, but the README published on the 2.0.0rc40 PyPI project page says is sufficient. The release-facing compatibility guidance can therefore identify a server as acceptable even though worker startup will reject it.

Acceptance criteria

• The repository README, PyPI project description, and generated API compatibility surface for the current Python SDK communicate a worker-protocol requirement that agrees semantically with the shipped SDK's authoritative protocol version and its qualified Server release.
• Release validation fails when customer-facing compatibility guidance advertises a lower or otherwise incompatible worker-protocol version; validation should compare the semantic contract, not prose wording, headings, or Markdown layout.
• The current prerelease guidance continues to distinguish SDK release identity, qualified Server release identity, and protocol compatibility without implying that RC sequence numbers must match.

Delete when

Delete when the source and published Python SDK compatibility surfaces no longer advertise protocol 1.1 for a release that requires 1.19, and the release gate prevents this semantic drift from recurring.

[rmcdaniel]

Additional acceptance criteria

Clarification: the stale published manifest named in the problem is worker_protocol.version: "1.1"; SDK 2.0.0-rc.40 requires worker protocol 1.19.

[rmcdaniel]

Current status: Approved and queued

This issue is approved and queued for implementation.