rename crates/ to engrams/, bindings/ to receptors/

- crates/ → engrams/ (Rust engrams live here)
- bindings/ → receptors/ (cross-language access points into the graph)
- Cargo.toml workspace paths updated

engram/receptors/go/engram_test.go

@@ -0,0 +1,130 @@
+// Package engram basic test.
+//
+// NOTE: This test requires the FFI shared library to be compiled first:
+//
+//	cargo build --package engram-ffi --release
+//
+// Then run:
+//
+//	DYLD_LIBRARY_PATH=../../target/release go test ./...
+//	# or on Linux:
+//	LD_LIBRARY_PATH=../../target/release go test ./...
+package engram
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+// TestOpenClose verifies that a database can be opened and closed without errors.
+func TestOpenClose(t *testing.T) {
+	dir := t.TempDir()
+	db, err := Open(filepath.Join(dir, "test-engram"))
+	if err != nil {
+		t.Fatalf("Open: %v", err)
+	}
+	defer db.Close()
+
+	n, err := db.NodeCount()
+	if err != nil {
+		t.Fatalf("NodeCount: %v", err)
+	}
+	if n != 0 {
+		t.Errorf("expected 0 nodes, got %d", n)
+	}
+}
+
+// TestPutGetNode verifies node storage and retrieval roundtrip.
+func TestPutGetNode(t *testing.T) {
+	dir := t.TempDir()
+	db, err := Open(filepath.Join(dir, "test-engram"))
+	if err != nil {
+		t.Fatalf("Open: %v", err)
+	}
+	defer db.Close()
+
+	input := &NodeInput{
+		Content:    "Spreading activation is the core retrieval mechanism",
+		NodeType:   "Concept",
+		Tier:       "Semantic",
+		Importance: 0.9,
+		Embedding:  []float32{0.1, 0.2, 0.3, 0.4},
+	}
+
+	id, err := db.PutNode(input)
+	if err != nil {
+		t.Fatalf("PutNode: %v", err)
+	}
+	if id == "" {
+		t.Fatal("expected non-empty UUID")
+	}
+
+	node, err := db.GetNode(id)
+	if err != nil {
+		t.Fatalf("GetNode: %v", err)
+	}
+	if node == nil {
+		t.Fatal("expected node, got nil")
+	}
+	if node.Content != input.Content {
+		t.Errorf("content mismatch: got %q, want %q", node.Content, input.Content)
+	}
+}
+
+// TestNodeCount verifies node count increments.
+func TestNodeCount(t *testing.T) {
+	dir := t.TempDir()
+	db, err := Open(filepath.Join(dir, "test-engram"))
+	if err != nil {
+		t.Fatalf("Open: %v", err)
+	}
+	defer db.Close()
+
+	for i := 0; i < 3; i++ {
+		_, err := db.PutNode(&NodeInput{
+			Content:   "node content",
+			Embedding: []float32{float32(i), 0.0, 0.0},
+		})
+		if err != nil {
+			t.Fatalf("PutNode[%d]: %v", i, err)
+		}
+	}
+
+	n, err := db.NodeCount()
+	if err != nil {
+		t.Fatalf("NodeCount: %v", err)
+	}
+	if n != 3 {
+		t.Errorf("expected 3 nodes, got %d", n)
+	}
+}
+
+// TestDecay verifies salience decay runs without error.
+func TestDecay(t *testing.T) {
+	dir := t.TempDir()
+	db, err := Open(filepath.Join(dir, "test-engram"))
+	if err != nil {
+		t.Fatalf("Open: %v", err)
+	}
+	defer db.Close()
+
+	_, err = db.PutNode(&NodeInput{
+		Content:   "test node",
+		Embedding: []float32{1.0, 0.0},
+	})
+	if err != nil {
+		t.Fatalf("PutNode: %v", err)
+	}
+
+	updated, err := db.Decay(0.95)
+	if err != nil {
+		t.Fatalf("Decay: %v", err)
+	}
+	if updated == 0 {
+		t.Error("expected at least one node to be decayed")
+	}
+}
+
+// ensure test file exists (compile guard)
+var _ = os.DevNull