expose metrics of karmada-metrics-adapter

[chaosi-zju]

What type of PR is this?

/kind feature

What this PR does / why we need it:

expose metrics of karmada-metrics-adapter

Which issue(s) this PR fixes:

Fixes part of #5954

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

`karmada-metrics-adapter`: Introduced `--metrics-bind-address` flag which will be used to expose Prometheus metrics.

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Codecov Report

Attention: Patch coverage is 0% with 26 lines in your changes missing coverage. Please review.

Project coverage is 48.37%. Comparing base (a891673) to head (c7009b2).

Files with missing lines	Patch %	Lines
cmd/metrics-adapter/app/options/options.go	0.00%	26 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6013      +/-   ##
==========================================
- Coverage   48.39%   48.37%   -0.03%     
==========================================
  Files         665      665              
  Lines       54811    54836      +25     
==========================================
  Hits        26525    26525              
- Misses      26568    26593      +25     
  Partials     1718     1718              

Flag	Coverage Δ
unittests	48.37% <0.00%> (-0.03%)	⬇️

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[RainbowMango]

/assign

[RainbowMango]

Have you tested it? Could you please share the test report?

[RainbowMango]

Release notes:

`karmada-metrics-adapter`: Introduced `--metrics-bind-address` flag which will be used to expose Prometheus metrics.

[RainbowMango]

/lgtm

[chaosi-zju]

Have you tested it? Could you please share the test report?

Yes, I tested for all four installation method

you can see test result in check metrics of metris-adapter step of the following ci task:

local up: https://github.com/chaosi-zju/karmada/actions/runs/12591245687/job/35094180733
helm: https://github.com/chaosi-zju/karmada/actions/runs/12591245693/job/35094072631

as for karmadactl and operator, I tested manually.

[RainbowMango]

OK I see. Thanks.
/approve

[karmada-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: RainbowMango

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