apis: add core sched apis

[saintube]

Ⅰ. Describe what this PR does

koordlet: add the apis for the Linux Core Scheduling feature.

Ⅱ. Does this pull request fix one issue?

Ⅲ. Describe how to verify it

Ⅳ. Special notes for reviews

V. Checklist

• I have written necessary docs and comments
• I have added necessary unit tests and integration tests
• All checks passed in make test

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (f197bbc) 66.03% compared to head (952d4d9) 66.06%.
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1720      +/-   ##
==========================================
+ Coverage   66.03%   66.06%   +0.03%     
==========================================
  Files         388      388              
  Lines       42314    42349      +35     
==========================================
+ Hits        27940    27977      +37     
+ Misses      12303    12301       -2     
  Partials     2071     2071              

Flag	Coverage Δ
unittests	66.06% <100.00%> (+0.03%)	⬆️

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[koordinator-bot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
To complete the pull request process, please assign fillzpp, jasonliu747 after the PR has been reviewed.
You can assign the PR to them by writing /assign @fillzpp @jasonliu747 in a comment when ready.

The full list of commands accepted by this bot can be found here.

Needs approval from an approver in each of these files:

• apis/OWNERS
• config/OWNERS
• pkg/koordlet/OWNERS
• pkg/util/OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[zwzhang0107]

/lgtm

[jasonliu747]

/lgtm

[eahydra]

/lgtm

[hormes]

/approve