feat: Wafer Map integration

## Backend — Session & playback
- Add SessionController (QML-facing live/review controller) with
  loadedFile property for active-file highlight binding
- Add SessionModel, FramePlayer, and CsvRecorder for state machine,
  frame seek/step/speed, and CSV recording
- Add SensorEditor for per-sensor value overrides (replace + offset)

src/pygui/serialcomm/stream_reader.py

@@ -0,0 +1,58 @@
+"""Continuos serial frame reader (Live-mode source)"""
+from __future__ import annotations
+import logging
+import threading
+from typing import Callable
+
+from pygui.backend.frame import Frame
+
+log = logging.getLogger(__name__)
+
+ParseLine = Callable[[str, int], Frame]
+
+class StreamReader:
+    
+    def __init__(self, transport, parse_line: ParseLine,
+                on_frame: Callable[[Frame], None],
+                on_error: Callable[[Exception], None] | None = None ) -> None:
+        self._transport = transport
+        self._parse = parse_line
+        self._on_frame = on_frame
+        self._on_error = on_error or (lambda e: None)
+        self._thread: threading.Thread | None = None
+        self._stop = threading.Event()
+        self._seq = 0
+        self.error_count = 0
+        
+    def start(self) -> None:
+        self._stop.clear()
+        self._thread = threading.Thread(target=self._run, daemon = True)
+        self._thread.start()
+
+    def _run(self) -> None:
+        try:
+            while not self._stop.is_set():
+                raw = self._transport.readline()
+                if not raw:
+                    continue
+                text = raw.decode(errors="ignore").strip()
+                if not text: 
+                    continue
+                try:
+                    frame= self._parse(text, self._seq)
+                    self._seq += 1
+                    self._on_frame(frame)
+                except Exception as exc:
+                    self.error_count += 1
+                    self._on_error(exc)
+        finally:
+            try:
+                self._transport.close()
+            except Exception:
+                pass
+            
+    def stop(self) -> None:
+        self._stop.set()
+        if self._thread is not None and self._thread.is_alive():
+            self._thread.join(timeout = 2.0)
+            self._thread = None