feat(go): persist full raw payload chunks

go/vehicle-gateway/internal/history/writer_test.go

@@ -54,6 +54,30 @@ func TestWriterAppendsRawLocationAndMileage(t *testing.T) {
 	}
 }
 
+func TestWriterChunksOversizedParsedJSON(t *testing.T) {
+	exec := &recordingExec{}
+	writer := NewWriter(exec)
+	env := sampleEnvelope()
+	env.Parsed = map[string]any{
+		"large_payload": strings.Repeat("x", 16_128),
+	}
+
+	if err := writer.AppendRawFrame(context.Background(), env); err != nil {
+		t.Fatalf("AppendRawFrame() error = %v", err)
+	}
+
+	rawInsert := findSQL(exec.calls, "INSERT INTO raw_")
+	if !strings.Contains(rawInsert, `"chunked":true`) || !strings.Contains(rawInsert, `"payload_kind":"parsed_json"`) {
+		t.Fatalf("raw insert should store a parsed_json chunk manifest: %s", rawInsert)
+	}
+	if got := countSQL(exec.calls, "USING raw_frame_payload_chunks"); got != 1 {
+		t.Fatalf("chunk child create count = %d", got)
+	}
+	if got := countSQL(exec.calls, "INSERT INTO chunk_"); got < 2 {
+		t.Fatalf("chunk insert count = %d, calls=%v", got, exec.calls)
+	}
+}
+
 func TestWriterSkipsSparseDerivedRows(t *testing.T) {
 	exec := &recordingExec{}
 	writer := NewWriter(exec)
@@ -87,6 +111,15 @@ func TestRawSizeBytesUsesRawTextWhenHexIsEmpty(t *testing.T) {
 	}
 }
 
+func TestSchemaStatementsCreateRawFramePayloadChunks(t *testing.T) {
+	statements := strings.Join(SchemaStatements("test_ts"), "\n")
+	for _, want := range []string{"raw_frame_payload_chunks", "payload_kind NCHAR(32)", "chunk_index INT", "chunk_text BINARY(16000)"} {
+		if !strings.Contains(statements, want) {
+			t.Fatalf("schema missing %q:\n%s", want, statements)
+		}
+	}
+}
+
 func sampleEnvelope() envelope.FrameEnvelope {
 	return envelope.FrameEnvelope{
 		Protocol:       envelope.ProtocolJT808,