Notify Feishu after Drone release results

[yaojin3616]

What changed

• Send a Feishu custom-bot notification for both successful and failed tag release pipelines.
• Send the success message only after the production restart and health check succeed.
• Send the failure message when image build, CI validation, transfer, restart, or health checks fail.
• Include the release tag, Drone build link, and short commit SHA in the notification.
• Validate both the HTTP response and Feishu's JSON code: 0 result.
• Read the webhook from the FEISHU_DEPLOY_WEBHOOK Drone repository secret instead of committing the credential.
• Document the new deployment behavior and required secret.

Why

Production deployments currently finish without proactively notifying the team. This reports both verified success and failures from any stage of the tag release pipeline.

Validation

• drone lint --trusted .github/drone.yml
• Local shell test for notification payload formatting
• Local shell tests for success and failure message formatting
• Local shell test for Feishu success-response matching
• Confirmed the supplied webhook token is absent from the repository diff
• git diff --check

Required Drone configuration

Add the supplied webhook URL as the FEISHU_DEPLOY_WEBHOOK repository secret before the next release tag. The Drone web session available during implementation was not authenticated, so the secret was intentionally not written through the UI or committed to Git.