enhance: [2.5] enable task delta cache

[bigsheeper]

When there are many segment tasks in the querycoord scheduler, the traversal in GetSegmentTaskDelta checks becomes time-consuming. This PR adds caching for segment deltas.

issue: #37630

pr: #39307

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[mergify]

@bigsheeper cpp-unit-test check failed, comment rerun cpp-unit-test can trigger the job again.

[mergify]

@bigsheeper go-sdk check failed, comment rerun go-sdk can trigger the job again.

[mergify]

@bigsheeper E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[bigsheeper]

rerun go-sdk

[bigsheeper]

/run-cpu-e2e

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.83%. Comparing base (e752059) to head (0580d97).

Additional details and impacted files

@@            Coverage Diff             @@
##              2.5   #39349      +/-   ##
==========================================
+ Coverage   80.99%   82.83%   +1.83%     
==========================================
  Files        1404     1104     -300     
  Lines      197531   170793   -26738     
==========================================
- Hits       159999   141476   -18523     
+ Misses      31898    23699    -8199     
+ Partials     5634     5618      -16     

Components	Coverage Δ
Client	78.26% <ø> (ø)
Core	∅ <ø> (∅)
Go	83.00% <100.00%> (+0.03%)	⬆️

Files with missing lines	Coverage Δ
internal/querycoordv2/task/scheduler.go	88.39% <100.00%> (+1.69%)	⬆️

... and 325 files with indirect coverage changes