enhance: clean up legacy storage v2

[shaoting-huang]

related: #39173

[mergify]

@shaoting-huang E2e jenkins job failed, comment /run-cpu-e2e can trigger the job again.

[mergify]

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 80.57%. Comparing base (c917fe4) to head (2e9516d).
Report is 6 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #39987      +/-   ##
==========================================
+ Coverage   79.76%   80.57%   +0.81%     
==========================================
  Files        1500     1464      -36     
  Lines      207393   205259    -2134     
==========================================
- Hits       165435   165397      -38     
+ Misses      35927    33857    -2070     
+ Partials     6031     6005      -26     

Components	Coverage Δ
Client	79.25% <ø> (ø)
Core	69.62% <ø> (ø)
Go	82.42% <ø> (+0.99%)	⬆️

see 37 files with indirect coverage changes

[shaoting-huang]

rerun go-sdk

[shaoting-huang]

/run-cpu-e2e

[tedxu]

/lgtm
/approve

[sre-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: shaoting-huang, tedxu

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