feat(simulator): add GUI runner, stubs, and workspace assets

Add host simulator scaffolding, examples, and docs so led-driver main can run end-to-end with MicroPython module stubs.

Co-authored-by: Cursor <cursoragent@cursor.com>

stubs/network.py

@@ -0,0 +1,38 @@
+"""Minimal `network` stub so imports succeed (led-simulator)."""
+
+STA_IF = 0
+AP_IF = 1
+
+# Fixed “STA” identity for hello.py / discovery on the host.
+_SIM_MAC = b"\xaa\xbb\xcc\xdd\xee\xff"
+
+
+class WLAN:
+    PM_NONE = 0
+
+    def __init__(self, interface):
+        self._interface = interface
+        self._active = False
+
+    def active(self, is_active=None):
+        if is_active is None:
+            return self._active
+        self._active = bool(is_active)
+        return None
+
+    def config(self, param=None, **kwargs):
+        if param == "mac":
+            return _SIM_MAC
+        return None
+
+    def connect(self, *args, **kwargs):
+        return None
+
+    def isconnected(self):
+        return True
+
+    def ifconfig(self, config_tuple=None):
+        if config_tuple is None:
+            # ip, subnet, gateway, dns — enough for hello UDP targets
+            return ("192.168.1.100", "255.255.255.0", "192.168.1.1", "8.8.8.8")
+        return None