optimize: add StateType Enum

[MaoMaoandSnail]

• I have registered the PR changes.

Ⅰ. Describe what this PR did

optimize: computeIfAbsent get twice
optimize: createProcessorController code order
optimize: add StateType Enum

Ⅱ. Does this pull request fix one issue?

Ⅲ. Why don't you add test cases (unit test/integration test)?

Ⅳ. Describe how to verify it

Ⅴ. Special notes for reviews

[codecov]

Codecov Report

Attention: Patch coverage is 40.22989% with 52 lines in your changes missing coverage. Please review.

Project coverage is 52.58%. Comparing base (34990eb) to head (90f9efc).
Report is 6 commits behind head on 2.x.

Files with missing lines	Patch %	Lines
...java/io/seata/saga/statelang/domain/StateType.java	0.00%	42 Missing ⚠️
.../saga/statelang/domain/impl/StateInstanceImpl.java	0.00%	4 Missing ⚠️
...ga/engine/store/db/DbAndReportTcStateLogStore.java	0.00%	2 Missing ⚠️
.../apache/seata/saga/statelang/domain/StateType.java	88.88%	1 Missing and 1 partial ⚠️
...io/seata/saga/statelang/domain/impl/StateImpl.java	0.00%	1 Missing ⚠️
...saga/statelang/domain/impl/LoopStartStateImpl.java	0.00%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #6891      +/-   ##
============================================
- Coverage     52.61%   52.58%   -0.04%     
- Complexity     6590     6599       +9     
============================================
  Files          1126     1128       +2     
  Lines         40004    40082      +78     
  Branches       4696     4703       +7     
============================================
+ Hits          21050    21076      +26     
- Misses        16946    16998      +52     
  Partials       2008     2008              

Files with missing lines	Coverage Δ
...he/seata/saga/statelang/domain/impl/BaseState.java	94.73% <ø> (ø)
...ta/saga/statelang/domain/impl/ChoiceStateImpl.java	89.47% <100.00%> (ø)
...omain/impl/CompensateSubStateMachineStateImpl.java	100.00% <100.00%> (ø)
...lang/domain/impl/CompensationTriggerStateImpl.java	100.00% <100.00%> (ø)
...a/saga/statelang/domain/impl/FailEndStateImpl.java	100.00% <100.00%> (ø)
...aga/statelang/domain/impl/ScriptTaskStateImpl.java	100.00% <100.00%> (ø)
...ga/statelang/domain/impl/ServiceTaskStateImpl.java	75.00% <100.00%> (ø)
.../saga/statelang/domain/impl/StateInstanceImpl.java	0.00% <ø> (ø)
...aga/statelang/domain/impl/SubStateMachineImpl.java	100.00% <100.00%> (ø)
...aga/statelang/domain/impl/SucceedEndStateImpl.java	100.00% <100.00%> (ø)
... and 10 more

... and 4 files with indirect coverage changes

[slievrly]

statelang/src/main/java/org/apache/seata/saga/statelang/parser/utils/StateMachineUtils.java:21:8: Unused import - org.apache.seata.saga.statelang.domain.StateType. [UnusedImports]

[slievrly]

LGTM