feat: allow selecting inner index label remap map (cherry-pick #1981 to 0.18)

[LHT129]

Summary

This is a cherry-pick of PR #1981 to branch 0.18.

Original PR: #1981

Changes from original PR:

• Add an inner-index label_remap_type parameter and expose it on the HGraph build parameter surface
• Encapsulate label remap storage inside LabelTable so inner indexes can switch between robin_map and robin_pg_map
• Add unit coverage for parameter parsing, HGraph mapping, and configurable remap behavior

Cherry-pick adaptations:

• Resolved conflicts in multiple files to adapt to 0.18 branch context
• Preserved all functionality from original PR
• Added necessary conflict resolution adjustments

Closes #1986 (original issue)

[gemini-code-assist]

Code Review

This pull request introduces a configurable label remapping mechanism within the LabelTable, allowing for different map implementations like PG and ROBIN. It refactors LabelTable to support hole management, adds a RemoveListFilter for tracking deletions, and updates HGraph and InnerIndex parameters accordingly. The review identifies several critical issues: the logic for RecoverRemove and IsTombstoneLabel is broken because MarkRemove no longer updates the remap table with tombstones; RemoveListFilter may lead to dangling references if it outlives the LabelTable; and MergeOther fails to merge deleted ID information. Additionally, the reviewer noted inefficient locking within a loop and several indentation violations of the style guide.

[codecov]

Codecov Report

❌ Patch coverage is 91.11111% with 12 lines in your changes missing coverage. Please review.

@@            Coverage Diff             @@
##             0.18    #2029      +/-   ##
==========================================
+ Coverage   90.82%   91.49%   +0.66%     
==========================================
  Files         330      330              
  Lines       19483    19574      +91     
==========================================
+ Hits        17696    17909     +213     
+ Misses       1787     1665     -122     

Flag	Coverage Δ
cpp	91.49% <91.11%> (+0.66%)	⬆️

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Components	Coverage Δ
common	85.94% <ø> (ø)
datacell	93.01% <ø> (+0.61%)	⬆️
index	91.69% <91.66%> (+0.71%)	⬆️
simd	100.00% <ø> (ø)

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[wxyucs]

lgtm