fix: move NAM block size sync before JACK client restart

The profile change handler was calling nam_host.set_block_size() AFTER
jack_client.start(), creating a race where the JACK callback fired with
the new buffer size while the old NAM subprocess was still running at
the old block_size. Pipe byte counts desynced => NAM returned passthrough.

+ also: auto_connect disable during restart, connect_fx_ports reorder,
  Tone3000 gear/sort/pagination params, NAM engine switch API endpoints

src/dsp/pipeline.py

@@ -21,7 +21,7 @@ from typing import Optional
 import numpy as np
 from scipy.signal import lfilter
 
-from .nam_engine_host import FastNAMHost
+from .nam_router import NAMEngineRouter
 from .ir_loader import IRLoader, IRFile
 from ..presets.types import FXBlock, FXType, Preset
 
@@ -302,10 +302,10 @@ class AudioPipeline:
 
     def __init__(
         self,
-        nam_host: Optional[FastNAMHost] = None,
+        nam_host: Optional[NAMEngineRouter] = None,
         ir_loader: Optional[IRLoader] = None,
     ):
-        self.nam = nam_host or FastNAMHost()
+        self.nam = nam_host or NAMEngineRouter()
         self.ir = ir_loader or IRLoader()
 
         # Signal chain — list of (FXType, enabled, bypass, params)