refactor: trigger auto dump by system memory usage

[fuyufjh]

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What's changed and what's your intention?

Use system memory provided by resource_util::memory::total_memory_used_bytes() instead of jemalloc statistics for more accurate auto dump triggering.

Follow-up of #13495 especially #13495 (comment).

By the way, rename src/common/src/monitor/process_linux.rs -> process.rs

Checklist

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• I have added necessary unit tests and integration tests
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[chenzl25]

LGTM!

[yuhao-su]

LGTM

[codecov]

Codecov Report

Attention: 28 lines in your changes are missing coverage. Please review.

Comparison is base (9c752e0) 68.30% compared to head (cca8cbb) 68.31%.
Report is 3 commits behind head on main.

Files	Patch %	Lines
src/common/heap_profiling/src/profiler.rs	0.00%	28 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #13685   +/-   ##
=======================================
  Coverage   68.30%   68.31%           
=======================================
  Files        1523     1523           
  Lines      261707   261693   -14     
=======================================
+ Hits       178768   178781   +13     
+ Misses      82939    82912   -27     

Flag	Coverage Δ
rust	68.31% <0.00%> (+<0.01%)	⬆️

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