issue: #51248
## What changed
- correct the omitted-`target_size` case to assert ordinary manual
compaction semantics
- add a physical Force Merge target-size case using persistent segment
IDs and MinIO insert-log sizes
- add deterministic Go boundary coverage for grouping selection at the
configured threshold and threshold + 1
- add target-size memory clamp coverage for cluster and standalone
co-location modes
- extend Optimize format, signed-int64 boundary, loaded-segment refresh,
and live async lifecycle coverage
- add the async Optimize wrapper and update the PyMilvus test dependency
to 3.1.0rc64
## Why
The previous cases did not prove that an explicit Force Merge target
affected physical output, assumed the wrong grouping threshold, and
depended on manual log inspection for algorithm selection. Loaded
refresh and the public async Optimize workflow also lacked live
end-to-end coverage.
The async case exposed milvus-io/pymilvus#3680 on PyMilvus 3.1.0rc62.
Version 3.1.0rc64 contains the tuple-unpacking fix and passes the
unmodified test.
## Validation
- all 10 planned case IDs pass; 0 failed and 0 blocked
- `milvus-dev-cli` Go UT job
`go-ut-local-zhuwenxi-zhuwenxing-i-4082040-30413568` succeeded; both
test functions and all five subtests passed
- physical target-size L3 case passed against a real cluster and MinIO
in 200.68s
- loaded refresh, target format/boundary, and manual compaction cases
passed against the same server version
- async Optimize L3 passed unmodified with PyMilvus 3.1.0rc64 in 56.91s
- 56 Python nodes collect successfully; Python compilation, Ruff, and
`git diff --check` pass
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Signed-off-by: zhuwenxing <wenxing.zhu@zilliz.com>
