[WIP] refactor: api machinary

[KevFan]

Based on top of #246

[codecov]

Codecov Report

Merging #251 (a9650b9) into main (f82291d) will decrease coverage by 1.45%.
The diff coverage is 72.94%.

@@            Coverage Diff             @@
##             main     #251      +/-   ##
==========================================
- Coverage   64.20%   62.75%   -1.45%     
==========================================
  Files          33       44      +11     
  Lines        3204     3235      +31     
==========================================
- Hits         2057     2030      -27     
- Misses        981     1037      +56     
- Partials      166      168       +2     

Flag	Coverage Δ
integration	67.74% <98.57%> (-3.47%)	⬇️
unit	58.34% <68.76%> (+0.82%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
api/v1beta1 (u)	∅ <ø> (∅)
pkg/common (u)	74.15% <47.36%> (-1.76%)	⬇️
pkg/istio (u)	30.24% <ø> (ø)
pkg/log (u)	31.81% <ø> (ø)
pkg/reconcilers (u)	38.38% <ø> (+4.69%)	⬆️
pkg/rlptools (u)	57.63% <ø> (ø)
controllers (i)	67.74% <98.57%> (-3.47%)	⬇️

Files	Coverage Δ
api/v1beta2/route_selectors.go	100.00% <100.00%> (ø)
controllers/authpolicy_auth_config.go	80.43% <100.00%> (+4.39%)	⬆️
...ntrollers/authpolicy_istio_authorization_policy.go	62.25% <100.00%> (-0.91%)	⬇️
...ollers/limitador_cluster_envoyfilter_controller.go	79.79% <100.00%> (-3.04%)	⬇️
controllers/ratelimitpolicy_controller.go	62.50% <100.00%> (-11.39%)	⬇️
controllers/ratelimitpolicy_limits.go	68.49% <100.00%> (-4.11%)	⬇️
controllers/ratelimitpolicy_wasm_plugins.go	78.02% <100.00%> (+0.24%)	⬆️
pkg/common/common.go	93.18% <100.00%> (+4.78%)	⬆️
pkg/common/k8s_utils.go	96.55% <ø> (-0.23%)	⬇️
pkg/library/common/domains.go	100.00% <100.00%> (ø)
... and 20 more

... and 3 files with indirect coverage changes

[KevFan]

Closing this and re-making a new PR instead on rebasing