[3.0] Multi Instances Related Refactor

[AlbumenJ]

What is the purpose of the change

• Refactor some ExtensionLoader usage
• Introduce Initializer for ScopeModel
• Add TCCL Changer
• remove some default model usage
• Remove Hessian2 TL

Brief changelog

Verifying this change

Checklist

• Make sure there is a GitHub_issue field for the change (usually before you start working on it). Trivial changes like typos do not require a GitHub issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue.
• Each commit in the pull request should have a meaningful subject line and body.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Check if is necessary to patch to Dubbo 3 if you are work on Dubbo 2.7
• Write necessary unit-test to verify your logic correction, more mock a little better when cross module dependency exist. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Add some description to dubbo-website project if you are requesting to add a feature.
• GitHub Actions works fine on your own branch.
• If this contribution is large, please follow the Software Donation Guide.

[codecov-commenter]

Codecov Report

Merging #8737 (eafdd42) into 3.0 (09f1f9a) will decrease coverage by 0.09%.
The diff coverage is 77.08%.

@@             Coverage Diff              @@
##                3.0    #8737      +/-   ##
============================================
- Coverage     63.72%   63.63%   -0.10%     
  Complexity      312      312              
============================================
  Files          1145     1149       +4     
  Lines         48182    48285     +103     
  Branches       7254     7281      +27     
============================================
+ Hits          30706    30727      +21     
- Misses        14108    14177      +69     
- Partials       3368     3381      +13     

Impacted Files	Coverage Δ
...bo/rpc/cluster/filter/support/ZoneAwareFilter.java	0.00% <0.00%> (ø)
...o/rpc/cluster/support/MergeableClusterInvoker.java	38.88% <0.00%> (-0.44%)	⬇️
...a/org/apache/dubbo/config/ReferenceConfigBase.java	70.54% <0.00%> (-0.56%)	⬇️
.../apache/dubbo/config/bootstrap/DubboBootstrap.java	69.82% <ø> (-0.24%)	⬇️
...apache/dubbo/metadata/MetadataServiceExporter.java	33.33% <0.00%> (ø)
.../dubbo/registry/client/DefaultServiceInstance.java	84.74% <ø> (-1.70%)	⬇️
...ubbo/registry/client/ServiceDiscoveryRegistry.java	82.00% <0.00%> (ø)
...stry/integration/AbstractConfiguratorListener.java	41.30% <0.00%> (-2.89%)	⬇️
...org/apache/dubbo/registry/nacos/NacosRegistry.java	0.00% <0.00%> (ø)
...org/apache/dubbo/registry/xds/util/XdsChannel.java	0.00% <0.00%> (ø)
... and 118 more

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