Fix authz during shutdown

[hzxuzhonghu]

…rontend map for xdp use

What type of PR is this?

What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #1381

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[Copilot]

Pull Request Overview

This PR refines the handling of unhealthy workloads by ensuring that such workloads are removed from the BPF endpoint map while remaining in the frontend/backend maps for authorization purposes. The changes include updating test assertions for workload status, refactoring the processor to call a new handler for unhealthy workloads, and adjusting logging levels and inline comments in BPF C code.

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
pkg/controller/workload/workload_processor_test.go	Updated tests to verify unhealthy workloads are removed from the endpoint map while retained in frontend/backend maps.
pkg/controller/workload/workload_processor.go	Introduced handleUnhealthyWorkload to manage unhealthy workloads and updated comments accordingly.
bpf/kmesh/workload/xdp.c	Changed log level from INFO to DEBUG in the xdp routine.
bpf/kmesh/workload/include/frontend.h	Updated inline comments to clarify that unhealthy backend status is not checked.

[Copilot]

Consider correcting 'donot' to 'do not' for improved clarity.

Suggested change

	if (direct_backend) { // in this case, we donot check the healthy status of the backend, just let it go
	if (direct_backend) { // in this case, we do not check the healthy status of the backend, just let it go

[codecov]

Codecov Report

Attention: Patch coverage is 70.00000% with 3 lines in your changes missing coverage. Please review.

Project coverage is 46.27%. Comparing base (3f0912e) to head (897be44).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/controller/workload/workload_processor.go	70.00%	2 Missing and 1 partial ⚠️

Files with missing lines	Coverage Δ
pkg/controller/workload/workload_processor.go	61.74% <70.00%> (+<0.01%)	⬆️

... and 1 file with indirect coverage changes

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[kmesh-bot]

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[kmesh-bot]

In response to a cherrypick label: new pull request created: #1400