Unify graceful shutdown interface, remove it from shutdown hook, execute on connection close

[EarthChen]

The read-only logic in the hook is removed due to two reasons: first, the read-only operation and graceful shutdown are already executed during connection closure; second, in the case of multiple protocols sharing a single port, invalid frames will be transmitted, leading to error reports on the peer end.

What is the purpose of the change?

Checklist

• Make sure there is a GitHub_issue field for the change.
• Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
• Write necessary unit-test to verify your logic correction. If the new feature or significant change is committed, please remember to add sample in dubbo samples project.
• Make sure gitHub actions can pass. Why the workflow is failing and how to fix it?

[codecov-commenter]

Codecov Report

❌ Patch coverage is 32.60870% with 62 lines in your changes missing coverage. Please review.
✅ Project coverage is 60.72%. Comparing base (49ecb04) to head (b176fee).
⚠️ Report is 22 commits behind head on 3.3.

Files with missing lines	Patch %	Lines
...g/transport/netty4/NettyPortUnificationServer.java	0.00%	16 Missing ⚠️
...e/dubbo/remoting/transport/netty4/NettyServer.java	0.00%	16 Missing ⚠️
...l/tri/transport/TripleServerConnectionHandler.java	0.00%	4 Missing and 1 partial ⚠️
.../exchange/support/header/HeaderExchangeServer.java	50.00%	3 Missing and 1 partial ⚠️
...g/apache/dubbo/rpc/protocol/tri/TripleInvoker.java	20.00%	2 Missing and 2 partials ⚠️
...o/rpc/protocol/tri/transport/GracefulShutdown.java	0.00%	4 Missing ⚠️
...pache/dubbo/remoting/transport/AbstractServer.java	0.00%	3 Missing ⚠️
...oting/exchange/support/ExchangeServerDelegate.java	0.00%	2 Missing ⚠️
...pache/dubbo/remoting/transport/ServerDelegate.java	0.00%	2 Missing ⚠️
...org/apache/dubbo/rpc/AbstractGracefulShutdown.java	77.77%	2 Missing ⚠️
... and 4 more

Additional details and impacted files

@@             Coverage Diff              @@
##                3.3   #15926      +/-   ##
============================================
- Coverage     60.74%   60.72%   -0.03%     
+ Complexity    11704    11703       -1     
============================================
  Files          1938     1942       +4     
  Lines         88694    88752      +58     
  Branches      13387    13396       +9     
============================================
+ Hits          53880    53891      +11     
- Misses        29285    29325      +40     
- Partials       5529     5536       +7     

Flag	Coverage Δ
integration-tests-java21	32.35% <32.60%> (-0.03%)	⬇️
integration-tests-java8	32.51% <32.60%> (+0.12%)	⬆️
samples-tests-java21	31.98% <26.08%> (-0.12%)	⬇️
samples-tests-java8	29.68% <26.08%> (+0.06%)	⬆️
unit-tests-java11	59.01% <17.39%> (-0.04%)	⬇️
unit-tests-java17	58.49% <17.39%> (-0.05%)	⬇️
unit-tests-java21	58.50% <17.39%> (-0.05%)	⬇️
unit-tests-java25	58.45% <17.39%> (-0.03%)	⬇️
unit-tests-java8	59.02% <17.39%> (-0.03%)	⬇️

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