issue: #50834
Fix no-index sealed vector raw data warmup selection. When a sealed
segment has no usable built or interim vector index, segcore now treats
raw vector field data as the vector search representation and resolves
its warmup from vector-index policy. Once a built or interim index
exists, raw vector data keeps normal vector-field warmup semantics.
Go load paths continue to pass field warmup unchanged; segcore resolves
the effective policy from current segment state.
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Signed-off-by: Shawn Wang <shawn.wang@zilliz.com>
