refactor(evidence): migrate runtime consumption (#29)

harness/tests/test_workflow_observable_contract.py

@@ -9,8 +9,8 @@ import pytest
 from tht.corpus.models import CanonicalDocument, CorpusManifest
 from tht.corpus.store import CorpusStore
 from tht.decisions import DecisionRecord, append_decision
+from tht.evidence import project_session
 from tht.phase import current_phase, effective_decisions
-from tht.session.artifacts import build_evidence_entries
 from tht.session.models import Candidate, SchemaLinking
 from tht.workflow import load_workflow
 
@@ -173,7 +173,7 @@ def test_schema_linking_evidence_used_resolves_from_the_active_canonical_corpus(
     )
     store.publish(generation)
 
-    entries = build_evidence_entries(
+    entries = project_session(
         [],
         _linking("evi-used"),
         tmp_path / "artifacts" / "evidence",
@@ -195,7 +195,7 @@ def test_legacy_evidence_without_a_canonical_corpus_keeps_used_and_reviewed_outc
     for evidence_id in ("evi-used", "evi-accepted", "evi-rejected"):
         (evidence_root / f"{evidence_id}.md").write_text(f"# {evidence_id}\n")
 
-    entries = build_evidence_entries(
+    entries = project_session(
         [
             _record(21, "evidence_accepted", "evi-accepted"),
             _record(22, "evidence_rejected", "evi-rejected"),