feat(scanner): Complete PoE implementation with Windows compatibility fix

- Fix namespace conflicts (Subgraph → PoESubgraph)
- Add hash sanitization for Windows filesystem (colon → underscore)
- Update all test mocks to use It.IsAny<>()
- Add direct orchestrator unit tests
- All 8 PoE tests now passing (100% success rate)
- Complete SPRINT_3500_0001_0001 documentation

Fixes compilation errors and Windows filesystem compatibility issues.
Tests: 8/8 passing
Files: 8 modified, 1 new test, 1 completion report

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

docs2/architecture/evidence-and-trust.md

@@ -0,0 +1,54 @@
+# Evidence and trust model
+
+## Determinism rules
+- Content-address all artifacts by digest.
+- Canonicalize JSON and sort arrays deterministically.
+- Use UTC timestamps only.
+- Do not use wall-clock or RNG in decision paths.
+- Pin inputs: analyzer versions, policy hash, advisory and VEX snapshots.
+
+## Evidence categories
+- Inputs: SBOMs, advisories, VEX statements, provenance, runtime facts.
+- Transforms: normalization outputs, linksets, reachability graphs.
+- Decisions: verdicts, explain traces, derived VEX.
+- Audit: token issuance, policy changes, signing events.
+
+## Decision Capsules
+A Decision Capsule is the minimal audit bundle for a decision. It includes:
+- The exact SBOM (inventory and usage views)
+- Advisory and VEX snapshot identifiers
+- Reachability evidence and unknowns metadata
+- Policy version and policy hash
+- Decision trace and derived VEX
+- DSSE envelopes and optional Rekor proofs
+
+## Attestation chain
+- in-toto statements wrapped in DSSE envelopes.
+- Signer produces DSSE; Attestor logs and verifies in Rekor when enabled.
+- Offline kits include cached proofs for air-gapped verification.
+
+## Aggregation-Only Contract (AOC)
+- Ingestion services store raw facts only.
+- No derived severity, consensus, or policy hints at ingest time.
+- All derived findings are produced by the Policy Engine.
+- Idempotent writes use content hash and supersedes chains.
+- Append-only revisions preserve upstream provenance and conflicts.
+
+## Content-addressed storage
+- RustFS stores SBOM fragments, reports, reachability graphs, and evidence bundles.
+- Replay bundles store inputs and outputs with deterministic ordering.
+
+## Replay bundles (typical layout)
+- manifest.json and manifest.dsse.json
+- input bundle with feeds, policy, and tool manifests
+- output bundle with SBOMs, findings, VEX, and logs
+
+## Verification steps (offline or online)
+1) Verify DSSE envelope signature against trusted keys.
+2) Recompute payload hash and compare to manifest digest.
+3) Verify Rekor proof when available or against offline checkpoints.
+4) Ensure all referenced CAS objects are present and hashed.
+
+## Retention
+- Evidence retention is configurable, but must preserve decision reproducibility
+  for the required audit window.