refactor(evidence): migrate acquisition and preprocessing (#30)

harness/tht/evidence/preprocessing.py

@@ -0,0 +1,44 @@
+"""Explicit construction boundary for Evidence preprocessing."""
+
+from typing import Protocol
+
+from tht.corpus.chunk import ChunkPolicy
+from tht.corpus.pipeline import CorpusPipeline
+from tht.corpus.store import CorpusStore
+from tht.evidence.contracts import EvidenceSource
+from tht.ports.vector import VectorStore
+
+
+class EvidenceEmbedder(Protocol):
+    def embed_documents(self, texts: list[str]) -> list[list[float]]: ...
+
+
+def build_preprocessing_pipeline(
+    *,
+    store: CorpusStore,
+    sources: list[EvidenceSource],
+    embedder: EvidenceEmbedder,
+    vector_store: VectorStore,
+    embedding_model: str,
+    embedding_dimensions: int,
+    chunk_policy: ChunkPolicy,
+    pipeline_version: str,
+    retain_published_generations: int = 3,
+    workspace_id: str | None = None,
+) -> CorpusPipeline:
+    """Construct preprocessing from the bounded infrastructure supplied by core."""
+    return CorpusPipeline(
+        store=store,
+        sources=sources,
+        embedder=embedder,
+        vector_store=vector_store,
+        embedding_model=embedding_model,
+        embedding_dimensions=embedding_dimensions,
+        chunk_policy=chunk_policy,
+        pipeline_version=pipeline_version,
+        retain_published_generations=retain_published_generations,
+        workspace_id=workspace_id,
+    )
+
+
+__all__ = ["EvidenceEmbedder", "build_preprocessing_pipeline"]