# Structured Provenance Hints for Unknowns

## Module
Unknowns

## Status
IMPLEMENTED

## Description
Structured provenance hint system for unknown binaries/components with typed hints (BuildIdMatch, DebugLink, ImportTableFingerprint, ExportTableFingerprint, SectionLayout, CompilerSignature, DistroPattern, VersionString, SymbolPattern), confidence scoring, and hypothesis generation for resolution (e.g., "Binary matches distro build-ID, likely backport").

## Implementation Details
- **Provenance Hint Builder**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Hints/ProvenanceHintBuilder.cs` -- fluent builder for constructing typed provenance hints with confidence scores; supports chaining multiple hint sources (build ID, debug link, import table, section layout) into a ranked hypothesis list.
- **IProvenanceHintBuilder Interface**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Hints/IProvenanceHintBuilder.cs` -- interface for the provenance hint builder, enabling dependency injection and testability.
- **Provenance Hint Model**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Models/ProvenanceHint.cs` -- data model for a single provenance hint containing hint type, source evidence, confidence score, and generated hypothesis text.
- **Provenance Hint Type**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Models/ProvenanceHintType.cs` -- enum defining all supported hint types: BuildIdMatch, DebugLink, ImportTableFingerprint, ExportTableFingerprint, SectionLayout, CompilerSignature, DistroPattern, VersionString, SymbolPattern.
- **Provenance Evidence**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Models/ProvenanceEvidence.cs` -- evidence payload associated with a provenance hint (e.g., the matched build ID string, the fingerprint hash, the compiler version string).
- **Native Unknown Context**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Models/NativeUnknownContext.cs` -- context model for native (C/C++/Rust/Go) unknown binaries, providing the binary analysis data that hint builders consume.
- **Native Unknown Classifier**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Services/NativeUnknownClassifier.cs` -- classifies unknown binaries by running all available hint builders and ranking hypotheses by confidence score.
- **Unknown Proof Emitter**: `src/Unknowns/__Libraries/StellaOps.Unknowns.Core/Services/UnknownProofEmitter.cs` -- emits attestation proofs for resolved unknowns, linking the provenance hints that led to identification.

## E2E Test Plan
- [ ] Build a provenance hint for a binary with a known GNU build-ID, invoke `ProvenanceHintBuilder` with BuildIdMatch type, and verify the hint contains the correct build ID, a confidence score > 0.8, and a hypothesis string mentioning the matched package
- [ ] Build hints for a binary with multiple evidence sources (build ID + section layout + compiler signature), and verify `NativeUnknownClassifier` ranks them by descending confidence score
- [ ] Submit a `NativeUnknownContext` for a binary with no matching evidence and verify the classifier returns an empty hint list with no false-positive hypotheses
- [ ] Build a DistroPattern hint for a binary matching a known distro build pattern (e.g., Debian hardening flags) and verify the hypothesis correctly identifies the distribution
- [ ] Resolve an unknown binary using provenance hints and verify `UnknownProofEmitter` produces an attestation proof linking the hints to the resolution decision
- [ ] Verify all `ProvenanceHintType` enum values have corresponding builder paths in `ProvenanceHintBuilder` by constructing one hint of each type and confirming no errors