[WIP] optimize: remove map iter codes and reuse delve api

[jayantxie]

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optimize

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 15 lines in your changes missing coverage. Please review.
✅ Project coverage is 3.30%. Comparing base (43514a0) to head (94f43fc).
⚠️ Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/proc/reference.go	0.00%	13 Missing ⚠️
pkg/proc/variables.go	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##            main     #52      +/-   ##
========================================
+ Coverage   2.64%   3.30%   +0.65%     
========================================
  Files         15      14       -1     
  Lines       2152    1726     -426     
========================================
  Hits          57      57              
+ Misses      2089    1663     -426     
  Partials       6       6              

Flag	Coverage Δ
unit	3.30% <0.00%> (+0.65%)	⬆️

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