feat(embedding,notes): implement ADR-0056 Blake3 stable hashing and ADR-0057 priority-aware retention

server/src/handlers/meta.rs

@@ -665,7 +665,20 @@ impl McpTool for TechDebtHandler {
                         effort_estimate: req.effort_estimate,
                     });
                     if debts.len() > 300 {
-                        debts.remove(0);
+                        let severity_rank = |sev: Option<&str>| match sev.unwrap_or("").to_lowercase().as_str() {
+                            "critical" => 4,
+                            "high" => 3,
+                            "medium" => 2,
+                            "low" => 1,
+                            _ => 1,
+                        };
+                        if let Some((idx_to_remove, _)) = debts.iter().enumerate().min_by_key(|(_, d)| {
+                            let status_score = if d.is_resolved { 0 } else { 10 };
+                            let sev_score = severity_rank(d.severity.as_deref());
+                            (status_score + sev_score, d.created_at)
+                        }) {
+                            debts.remove(idx_to_remove);
+                        }
                     }
                 });
                 Ok("Tech debt logged".to_string())
@@ -2827,4 +2840,4 @@ mod tests {
             .unwrap();
         assert!(pre_res.contains("active_tasks"));
     }
-}
+