v2 Phase 6 (step 1): Home Assistant REST client + live self-test

daemon/ha_client.py: HAClient (brightness, color_temp, on/off, state snapshot)
over the HA REST API with smooth `transition`; token is read from a local
%LOCALAPPDATA%\Clawdmeter\ha_config.json and is never logged. Verified
end-to-end against a real Gledopto GL-C-006P tunable-white dimmer.

ha_config.example.json is the committed template; the real config (with the
token) lives outside the repo and is .gitignored as a safety net.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

daemon/ha_config.example.json

@@ -0,0 +1,6 @@
+{
+  "_comment": "Home Assistant config for Clawdmeter Phase 6. COPY this file to %LOCALAPPDATA%\\Clawdmeter\\ha_config.json and fill in url + token. The real file lives OUTSIDE the repo so the token is never committed. token = a Home Assistant Long-Lived Access Token (HA -> your profile -> Security -> Create Token).",
+  "url": "http://homeassistant.local:8123",
+  "token": "PASTE_LONG_LIVED_ACCESS_TOKEN_HERE",
+  "entities": ["light.dimmer_v_spalne"]
+}