Add Pico UART client and tests

pico-dashboard/comms/uart_client.py

@@ -0,0 +1,40 @@
+import json
+
+
+class UartClient:
+    def __init__(self, uart):
+        self.uart = uart
+        self.buffer = ""
+
+    def send_message(self, message):
+        payload = json.dumps(message, separators=(",", ":")) + "\n"
+        self.uart.write(payload.encode("utf-8"))
+
+    def read_available_messages(self):
+        messages = []
+
+        while self.uart.any():
+            chunk = self.uart.read()
+
+            if not chunk:
+                break
+
+            self.buffer += chunk.decode("utf-8")
+
+            while "\n" in self.buffer:
+                line, self.buffer = self.buffer.split("\n", 1)
+                line = line.strip()
+
+                if not line:
+                    continue
+
+                try:
+                    messages.append(json.loads(line))
+                except ValueError:
+                    messages.append({
+                        "type": "error",
+                        "message": "invalid_json",
+                        "raw": line,
+                    })
+
+        return messages