logpuller: simplify region failure handling pipeline

[lidezhu]

What problem does this PR solve?

Issue Number: close #5612

What is changed and how it works?

This pull request simplifies the region failure handling pipeline in the logpuller component. By removing unnecessary concurrency primitives like errgroup and dedicated error channels, the implementation becomes more straightforward and easier to maintain. The changes focus on improving how cached errors are processed, ensuring efficient batch handling and proper resource management during shutdown.

Highlights

• Pipeline Simplification: Removed the errCh channel and the errgroup usage in regionFailureHandler.Run, replacing them with a more direct polling and notification mechanism.
• Error Handling Optimization: Refactored the error cache processing to use a ticker and a notification channel, reducing complexity and potential lock contention.
• Testing Improvements: Added a new test file logservice/logpuller/region_failure_handler_test.go and removed outdated tests in subscription_client_test.go to reflect the new architecture.

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Questions

Will it cause performance regression or break compatibility?

Do you need to update user documentation, design documentation or monitoring documentation?

Release note

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Review details

⚙️ Run configuration

Configuration used: Organization UI

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Run ID: 0b8d6a36-c410-49e4-ab83-eb444447df41

📥 Commits

Reviewing files that changed from the base of the PR and between 1971d2b and 075d517.

📒 Files selected for processing (3)

• logservice/logpuller/region_failure_handler.go
• logservice/logpuller/region_failure_handler_test.go
• logservice/logpuller/subscription_client_test.go

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch ldz/refactor-puller03

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[gemini-code-assist]

Code Review

This pull request refactors the regionFailureHandler to simplify error handling by removing the background dispatcher goroutine and the errCh channel, instead processing cached errors directly in the main loop of Run using a ticker and a ready notification channel. Additionally, new unit tests are introduced to verify the error cache and handler behavior, while obsolete tests are removed. The reviewer suggests refactoring the inline closure handleCachedErrors into a dedicated method on regionFailureHandler to improve readability and performance, and increasing the timeout in require.Eventually in the test to 5 seconds to prevent flaky test failures in CI/CD environments.

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[ti-chi-bot]

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[lidezhu]

/test all