[fix] (cloud) Fix local/remote tablet size semantics in schema views(#60887)

[deardeng]

cherry-pick from #60887

In storage-compute separation, data size should be represented consistently as remote size.

Previously, show tablets and information_schema.partitions could diverge from information_schema.backend_tablets, which made local/remote semantics confusing for users and operators.

This change aligns cloud-mode output mapping for local/remote size columns and adds a regression test to guard the behavior.

(cherry picked from commit 17617be)

What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

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Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
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    • Previous test can cover this change.
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• Behavior changed:

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  • Yes.

• Does this need documentation?

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[deardeng]

run buildall

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FE UT Coverage Report

Increment line coverage 79.49% (31/39) 🎉
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Complete coverage report

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FE Regression Coverage Report

Increment line coverage 92.31% (36/39) 🎉
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