fix: Unify hook singleton implementation in proxy

[congqixia]

Related to #34885

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[codecov]

Codecov Report

Attention: Patch coverage is 68.75000% with 10 lines in your changes missing coverage. Please review.

Project coverage is 71.87%. Comparing base (c339df2) to head (d808367).
Report is 39 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #34887      +/-   ##
==========================================
- Coverage   80.84%   71.87%   -8.98%     
==========================================
  Files        1175     1185      +10     
  Lines      142066   142718     +652     
==========================================
- Hits       114854   102576   -12278     
- Misses      22822    35729   +12907     
- Partials     4390     4413      +23     

Files	Coverage Δ
internal/proxy/hook_interceptor.go	100.00% <100.00%> (ø)
internal/proxy/impl.go	86.25% <100.00%> (ø)
internal/proxy/proxy.go	70.34% <100.00%> (-0.12%)	⬇️
internal/proxy/util.go	91.65% <100.00%> (-0.01%)	⬇️
internal/util/hookutil/default.go	100.00% <ø> (ø)
tests/integration/minicluster_v2.go	72.72% <100.00%> (ø)
internal/util/hookutil/hook.go	50.81% <54.54%> (+4.15%)	⬆️

... and 268 files with indirect coverage changes

[aoiasd]

/lgtm