feat: add AuthProviderBlock layout block support

[WilliamBergamin]

Summary

This pull request adds the auth_provider layout block as AuthProviderBlock, matching slackapi/java-slack-sdk#1659 and slackapi/node-slack-sdk#2778.

• Block.parse returns an AuthProviderBlock instead of skipping it as an unknown block.

Testing

With an app that has features.user_connections and the Home tab enabled:

from slack_sdk.models.blocks import AuthProviderBlock
from slack_sdk.models.views import View

client.views_publish(
    user_id=user_id,
    view=View(
        type="home",
        blocks=[
            AuthProviderBlock(
                value="my-provider",
                name="My Provider",
                is_connected=False,
                auth_url="https://example.com/oauth/start",
            )
        ],
    ),
)

1. Open the app's Home tab and confirm the provider renders with a Connect button.
2. Publish again with is_connected=True, a connected_identity, and an overflow accessory; confirm the connected state and menu render.

Ran these steps with a Bolt app on a sandbox. Each views_publish response's blocks parse back to AuthProviderBlock, including Slack's added context block in fallback.

Category

• slack_sdk.web.WebClient (sync/async) (Web API client)
• slack_sdk.webhook.WebhookClient (sync/async) (Incoming Webhook, response_url sender)
• slack_sdk.socket_mode (Socket Mode client)
• slack_sdk.signature (Request Signature Verifier)
• slack_sdk.oauth (OAuth Flow Utilities)
• slack_sdk.models (UI component builders)
• slack_sdk.scim (SCIM API client)
• slack_sdk.audit_logs (Audit Logs API client)
• slack_sdk.rtm_v2 (RTM client)
• /docs (Documents)
• /tutorial (PythOnBoardingBot tutorial)
• tests/integration_tests (Automated tests for this library)

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.
• I've run python3 -m venv .venv && source .venv/bin/activate && ./scripts/run_validation.sh after making the changes.

🤖 Generated with Claude Code

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.35%. Comparing base (8fe5157) to head (0d90636).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1985      +/-   ##
==========================================
+ Coverage   84.25%   84.35%   +0.10%     
==========================================
  Files         118      118              
  Lines       13730    13793      +63     
==========================================
+ Hits        11568    11635      +67     
+ Misses       2162     2158       -4     

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

[zimeg]

🧠 🔏 @WilliamBergamin Most exciting a feature