feat(fx): Phase 1 DAW chain hop nhat — fx_realtime chain JSON giu thu tu, SET_PARAM/REPORT_LATENCY qua WS text, native_render chain builtin+vst3 xen ke, pytest

app/core/native_render.py

@@ -232,6 +232,8 @@ def render_fx_chain(input_wav, fx_chain, sample_rate, out_path=None) -> str:
         )
     slots = []
     for fx in fx_chain or []:
+        if not isinstance(fx, dict) or fx.get("active") is False:
+            continue
         typ = fx.get("type")
         if typ == "vst3":
             p = (fx.get("path") or "").strip()
@@ -244,7 +246,15 @@ def render_fx_chain(input_wav, fx_chain, sample_rate, out_path=None) -> str:
             slots.append({"type": "vst3", "path": resolved,
                           "preset_b64": fx.get("preset_b64", "") or "",
                           "bypass": bool(fx.get("bypass"))})
+        elif typ in ("eq", "eqpro", "imager", "maximizer", "compressor",
+                     "limiter", "exciter", "rebalance"):
+            # Builtin DSP — chain hợp nhất (spec PLAN_DAW_A.md Phase 1). C++
+            # RenderFxJob xử lý theo id/params (Phase 2); giữ NGUYÊN thứ tự.
+            slots.append({"type": "builtin", "id": typ,
+                          "params": dict(fx.get("params") or {}),
+                          "bypass": bool(fx.get("bypass"))})
         elif typ == "builtin":
+            # Legacy: {type: builtin, id: gain} — giữ cho project cũ.
             slots.append({"type": "builtin", "id": fx.get("id", "gain"),
                           "params": dict(fx.get("params") or {}),
                           "bypass": bool(fx.get("bypass"))})