enhance: [2.5] Add metrics for parse expression

[xiaocai2333]

master pr: #39654

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[mergify]

@xiaocai2333 go-sdk check failed, comment rerun go-sdk can trigger the job again.

[codecov]

Codecov Report

Attention: Patch coverage is 92.85714% with 1 line in your changes missing coverage. Please review.

Project coverage is 81.04%. Comparing base (4a8e6fc) to head (8ebec56).

Files with missing lines	Patch %	Lines
internal/proxy/task_query.go	83.33%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##              2.5   #39716      +/-   ##
==========================================
+ Coverage   81.02%   81.04%   +0.01%     
==========================================
  Files        1415     1415              
  Lines      198870   198885      +15     
==========================================
+ Hits       161138   161181      +43     
+ Misses      32066    32052      -14     
+ Partials     5666     5652      -14     

Components	Coverage Δ
Client	78.26% <ø> (ø)
Core	69.46% <ø> (ø)
Go	83.01% <92.85%> (+0.01%)	⬆️

Files with missing lines	Coverage Δ
internal/proxy/task_delete.go	90.33% <100.00%> (+0.07%)	⬆️
internal/proxy/task_search.go	76.59% <100.00%> (+0.08%)	⬆️
pkg/metrics/proxy_metrics.go	100.00% <100.00%> (ø)
internal/proxy/task_query.go	80.71% <83.33%> (+0.02%)	⬆️

... and 28 files with indirect coverage changes