chore(kuma-cp) split listener configurers across source files

[jpeach]

Summary

Split the listener configurers into separate source files for
listeners and filter chains to make them a bit easier to find.
Remove the unnecessary ListenerFilterChainConfigurerV3 types.

Full changelog

N/A

Issues resolved

N/A

Documentation

N/A

Testing

• Unit tests
• E2E tests
• Manual testing on Universal
• Manual testing on Kubernetes

Backwards compatibility

• Add backport-to-stable label if the code is backwards compatible. Otherwise, list breaking changes.

[codecov-commenter]

Codecov Report

Merging #2592 (8ecde73) into master (a0c9132) will increase coverage by 0.07%.
The diff coverage is 96.22%.

@@            Coverage Diff             @@
##           master    #2592      +/-   ##
==========================================
+ Coverage   52.19%   52.27%   +0.07%     
==========================================
  Files         869      869              
  Lines       48595    48593       -2     
==========================================
+ Hits        25366    25401      +35     
+ Misses      21184    21148      -36     
+ Partials     2045     2044       -1     

Impacted Files	Coverage Δ
...kg/xds/envoy/listeners/filter_chain_configurers.go	97.27% <ø> (ø)
pkg/xds/envoy/listeners/listener_configurers.go	96.22% <96.22%> (ø)
api/observability/v1/mads.pb.go	35.56% <0.00%> (+1.03%)	⬆️
pkg/xds/generator/direct_access_proxy_generator.go	83.90% <0.00%> (+1.14%)	⬆️
pkg/insights/resyncer.go	65.81% <0.00%> (+1.70%)	⬆️
pkg/mads/server/server.go	84.82% <0.00%> (+1.78%)	⬆️
pkg/mads/v1/client/client.go	43.75% <0.00%> (+2.50%)	⬆️
app/kumactl/cmd/root.go	73.68% <0.00%> (+3.50%)	⬆️
pkg/plugins/resources/memory/store.go	82.06% <0.00%> (+4.34%)	⬆️
... and 4 more

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