feat: native WireView Pro II monitoring (detection, serial protocol, live tab)

Standalone support for the ThermalGrizzly WireView Pro II without
depending on the external wireview_reporter exporter:

- wireview.py: serial protocol (STX/ETX + 16-bit CRC16-CCITT) with
  vendor-data product identification, config version, UID, build
  string, screen layout, and temperature/power/current sensor reads;
  hwmon fallback with per-channel index resolution; udev-based
  detection (vendor 0x2560 / product 0x0101) with fallback port
  probing; serial read timeout and watchdog reconnect
- server.py: startup detection (root only), 1 Hz poller gated on
  subscribed clients, WS 'wireview' channel, GET /api/wireview,
  rejected-product memoization, stale-read race guard
- frontend: WireView tab (visible when a device is detected) with
  live temperature/power/current cards, sparkline history, and
  device info; nullable temp channels
- tests: 76 tests covering parser, CRC, fault classification,
  hwmon resolution, JSON safety, and the serial transport against
  a pty-based fake device

Verified live: tab appears with the device connected, disappears
when unplugged, reconnects on re-plug, no serial traffic when idle.

Makefile

@@ -25,6 +25,7 @@ dev: ## Create/refresh the dev environment (uv sync)
 test: ## Run the test suite
 	$(UV) run python tests/test_security.py
 	$(UV) run python tests/test_rm_power.py
+	$(UV) run python tests/test_wireview.py
 
 clean: ## Remove build artifacts
 	rm -rf frontend/dist frontend/node_modules