feat: implement provenance tagging and poisoning protection (issue #33)

services/memory/src/retrieval/mod.rs

@@ -14,6 +14,8 @@ pub mod stage4;
 
 use std::collections::HashMap;
 
+use crate::provenance::ProvenanceRecord;
+
 /// A candidate memory entry passing through the retrieval pipeline.
 /// Carries accumulated scores from each stage.
 #[derive(Debug, Clone)]
@@ -46,6 +48,8 @@ pub struct RetrievalCandidate {
     pub corpus_score: f32,
     /// Combined/final score after all stages.
     pub final_score: f32,
+    /// Provenance metadata loaded from the provenance table.
+    pub provenance_metadata: Option<ProvenanceRecord>,
 }
 
 /// Parameters controlling the staged retrieval pipeline.
@@ -61,6 +65,10 @@ pub struct RetrievalParams {
     pub tag_filter: Option<String>,
     /// Final result limit (from `QueryMemoryRequest.limit`, defaults to 5).
     pub result_limit: u32,
+    /// Minimum trust level for provenance filtering.
+    pub min_trust_level: Option<i32>,
+    /// Whether to exclude revoked memories from results.
+    pub exclude_revoked: bool,
 }
 
 impl RetrievalParams {
@@ -76,6 +84,8 @@ impl RetrievalParams {
             relevance_threshold: config.relevance_threshold,
             tag_filter,
             result_limit: if result_limit == 0 { 5 } else { result_limit },
+            min_trust_level: None,
+            exclude_revoked: true,
         }
     }
 }