Fix pg membership inconsistency

[yuwmao]

• Implement on_pg_clean_replace_member_task callback which actually rollback the membership change
• Add a reconcile_membership API which is used to correct the existing inconsistency problem.

Rely on eBay/HomeStore#856

[codecov-commenter]

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Codecov Report

❌ Patch coverage is 0% with 72 lines in your changes missing coverage. Please review.
✅ Project coverage is 55.86%. Comparing base (1746bcc) to head (aff362e).
⚠️ Report is 147 commits behind head on main.

Files with missing lines	Patch %	Lines
src/lib/homestore_backend/hs_pg_manager.cpp	0.00%	52 Missing ⚠️
src/lib/homestore_backend/hs_http_manager.cpp	0.00%	18 Missing ⚠️
...ib/homestore_backend/replication_state_machine.cpp	0.00%	2 Missing ⚠️
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Additional details and impacted files

@@            Coverage Diff             @@
##             main     #386      +/-   ##
==========================================
- Coverage   63.15%   55.86%   -7.29%     
==========================================
  Files          32       35       +3     
  Lines        1900     4942    +3042     
  Branches      204      625     +421     
==========================================
+ Hits         1200     2761    +1561     
- Misses        600     1888    +1288     
- Partials      100      293     +193     

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[JacksonYao287]

LGTM

[JacksonYao287]

nit, suggest using get_pg_id_with_group_id instead of a loop here

[xiaoxichen]

We have 4 similar API hook functions

1. on_pg_start_replace_member
2. on_pg_complete_replace_member
3. reconcile_membership
4. on_pg_clean_replace_member_task

all of them are trying to maintain the PG superblok in sync with actual raft membership.

So which layer maintain the source of truth ? It seems to me like the HS is the source of truth as in PG creation the PG superblock is the last one get written , pg move also sharing similar pattern.

If HS is the source of truth , can we consolidate all the API into "update_membership" ?

API hooks can still there, just trying to avoid PG superblk manage code is written several times