bugfix: ensure environment is fully loaded before ConfigurationFactory initialization

[WangzJi]

fixes: #7641

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Ⅰ. Describe what this PR did

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

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 61.42%. Comparing base (d239a81) to head (34e4cdb).

Additional details and impacted files

@@             Coverage Diff              @@
##                2.x    #7705      +/-   ##
============================================
+ Coverage     61.38%   61.42%   +0.03%     
- Complexity      684      688       +4     
============================================
  Files          1323     1323              
  Lines         49943    49941       -2     
  Branches       5885     5884       -1     
============================================
+ Hits          30657    30675      +18     
+ Misses        16524    16508      -16     
+ Partials       2762     2758       -4     

Files with missing lines	Coverage Δ
...ot/autoconfigure/loader/SeataPropertiesLoader.java	63.88% <100.00%> (+0.73%)	⬆️

... and 12 files with indirect coverage changes

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[funky-eyes]

Can you explain why this change was made?
What's the difference between setting the environment only when it's empty and setting it unconditionally (without checking for emptiness)?

[WangzJi]

@funky-eyes Thanks for the review!

The key point: Line 64 triggers ConfigurationFactory static initialization, which needs a complete environment.

With the old null check:

• EnvironmentPostProcessor sets environment (without application.properties in Spring Cloud)
• ApplicationContextInitializer skips updating (due to null check)
• ConfigurationFactory gets incomplete environment → can't read seata.config.type from application.properties

Unconditional update ensures:

• Always use ApplicationContextInitializer's environment (which has all property sources loaded)
• Safe because it's always more complete than EnvironmentPostProcessor's

This explains why bootstrap.yml workaround works - it's loaded early enough.

[funky-eyes]

So, in Spring Cloud there can be multiple Environment instances, which is why the environment may be incomplete. Otherwise, as I understand it, the same instance shouldn't have this problem, right?