[Store] Prevent drain success with local disk replicas

[feichai0017]

Description

Fixes #2817.

Prevent drain jobs from reporting success while LOCAL_DISK replicas remain on clients that own source segments:

• Capture source segment ownership when the drain job is created.
• Treat unsupported local-disk moves as terminal failures, restore source segments to OK, and return an explicit error.
• Keep existing memory-replica migration behavior unchanged.
• Add regression coverage for a local-disk-only object.

This change fails closed; it does not add cross-node local-disk migration.

Module

• Mooncake Store (mooncake-store)

Type of Change

• Bug fix

How Has This Been Tested?

Test commands:

./scripts/code_format.sh --check -b upstream/main
SKIP=mooncake-code-format pre-commit run --files mooncake-store/include/master_service.h mooncake-store/src/master_service.cpp mooncake-store/tests/master_service_test.cpp
cmake --build build --target master_service_test
./build/mooncake-store/tests/master_service_test

Test results:

• Unit tests pass (142/142 on Ubuntu)
• Integration tests pass (not applicable)
• Manual testing done

Checklist

• I have performed a self-review of my own code
• I have formatted my code using ./scripts/code_format.sh
• I have run pre-commit on the touched files and all applicable hooks pass
• I have updated the documentation (not applicable; no user-facing API change)
• I have added tests to prove my changes are effective
• For changes >500 LOC: I have filed an RFC issue (not applicable; under 500 LOC)

AI Assistance Disclosure

• AI tools were used: Codex assisted with review, formatting, and test execution.

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[gemini-code-assist]

Code Review

This pull request introduces handling for unsupported LOCAL_DISK replicas during drain jobs. Since LOCAL_DISK replicas are client-scoped and cannot currently be migrated, the system now identifies them, associates them with the source segments owned by the client, and fails the drain job. A new unit test has been added to verify this failure behavior. I have no additional feedback to provide as there are no review comments.

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[codecov-commenter]

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Codecov Report

❌ Patch coverage is 93.47826% with 6 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
mooncake-store/src/master_service.cpp	88.46%	6 Missing ⚠️

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