feat: expand companion platform, device controls, and memoir workflows

Add customer and operator login, BLE provisioning, device fleet controls, call memory, memoir generation, and refreshed family and maintenance portals. Include API contracts, migrations, firmware sources, tests, assets, and deployment documentation.

firmware/echoear-platform-agent/tools/test_elder_chat.py

@@ -0,0 +1,38 @@
+"""Explicit USB-only smoke test: request a fixed sentence, then hang up."""
+import argparse
+import time
+import serial
+
+p = argparse.ArgumentParser()
+p.add_argument("--port", default="COM6")
+p.add_argument("--seconds", type=int, default=60)
+args = p.parse_args()
+port = serial.Serial()
+port.port, port.baudrate, port.timeout = args.port, 115200, 0.2
+port.dtr = port.rts = False
+port.open()
+markers = ("PLATFORM_HTTP", "Platform error code:", "call_client:", "USB diagnostic:",
+           "RTC", "rtc", "volc_start", "PLAYBACK", "DOWNLINK", "AUDIO conversation", "on_volc", "rst:",
+           "panic", "Rebooting", "assert failed", "Guru Meditation", "conv_ai_service", "ERR|", "volc_conv.c",
+           "Backtrace", "PC      :", "EXCVADDR", "A0      :", "Core  1 register")
+try:
+    print("Starting explicit USB test conversation", flush=True)
+    port.write(b"diag-say\n")
+    started = time.monotonic()
+    stopped = False
+    diagnosed = False
+    while time.monotonic() - started < args.seconds:
+        if not diagnosed and time.monotonic() - started >= 10:
+            port.write(b"diag-state\n")
+            diagnosed = True
+        if not stopped and time.monotonic() - started >= args.seconds - 15:
+            port.write(b"diag-stop\n")
+            stopped = True
+            print("Requested hangup", flush=True)
+        line = port.readline().decode(errors="replace").strip()
+        if line and any(m in line for m in markers):
+            print(line, flush=True)
+finally:
+    if not stopped:
+        port.write(b"diag-stop\n")
+    port.close()