fix(evidence): bound project filters to FTS candidates

engines/evidence-ledger/internal/app/app.go

@@ -1824,6 +1824,8 @@ func buildSearchQuery(opts SearchOpts) (string, []any) {
 	where, params := appendSearchResultFilters(opts, []string{"1=1"}, params)
 	params = append(params, limit)
 
+	// CROSS JOIN pins the candidate pool as the outer loop. A reorder through
+	// sources and items evaluates correlated filters against the whole archive.
 	sqlText := `with fts_candidates as materialized (
   select item_id, snippet(item_fts, 5, '[', ']', '...', 20) as snippet, bm25(item_fts) as fts_score
   from item_fts
@@ -1833,7 +1835,7 @@ func buildSearchQuery(opts SearchOpts) (string, []any) {
 )
 select i.id, s.kind, c.name, c.kind, i.kind, coalesce(a.type,''), coalesce(a.name,''), coalesce(i.created_at,''), fc.snippet, printf('%.6f', fc.fts_score), i.content_hash
 from fts_candidates fc
-join items i on i.id = fc.item_id
+cross join items i on i.id = fc.item_id
 join sources s on s.id = i.source_id
 join collections c on c.id = i.collection_id
 left join actors a on a.id = i.actor_id

engines/evidence-ledger/internal/app/app_test.go

@@ -1855,6 +1855,11 @@ values(?,?,?,?,?,?,?,?,?,?)`, id, "source-1", "collection-1", "actor-1", id, "me
 			}
 		}
 	}
+	if _, err := db.Exec(`insert into item_metadata(item_id, key, value) values
+('item-000','project','escoffier-labs/brigade'),
+('item-001','cwd','/workspace/brigade')`); err != nil {
+		t.Fatal(err)
+	}
 }
 
 func explainPlan(t *testing.T, db *sql.DB, sqlText string, args ...any) string {
@@ -2018,6 +2023,38 @@ func TestSearchPlanBoundsFTSCandidatesBeforeJoins(t *testing.T) {
 		}
 	}
 
+	projectSQL, projectParams := buildSearchQuery(SearchOpts{Query: "needle", Project: "workspace", Limit: 5})
+	projectPlan := explainPlan(t, db, projectSQL, projectParams...)
+	for _, want := range []string{
+		"SCAN fc",
+		"SEARCH i USING",
+		"SEARCH im USING COVERING INDEX",
+		"(item_id=?",
+	} {
+		if !strings.Contains(projectPlan, want) {
+			t.Fatalf("project filter plan missing %q:\n%s", want, projectPlan)
+		}
+	}
+	if strings.Index(projectPlan, "SCAN fc") > strings.Index(projectPlan, "SEARCH i USING") {
+		t.Fatalf("project filter plan does not keep FTS candidates outermost:\n%s", projectPlan)
+	}
+
+	exactProject, err := search(db, SearchOpts{Query: "needle", Project: "escoffier-labs/brigade", Limit: 5})
+	if err != nil {
+		t.Fatalf("exact project search: %v", err)
+	}
+	if len(exactProject) != 1 || exactProject[0].ID != "item-000" {
+		t.Fatalf("exact project results = %#v, want item-000", exactProject)
+	}
+
+	substringProject, err := search(db, SearchOpts{Query: "needle", Project: "workspace/brigade", Limit: 5})
+	if err != nil {
+		t.Fatalf("substring project search: %v", err)
+	}
+	if len(substringProject) != 1 || substringProject[0].ID != "item-001" {
+		t.Fatalf("substring project results = %#v, want item-001", substringProject)
+	}
+
 	results, err := search(db, opts)
 	if err != nil {
 		t.Fatalf("search: %v", err)