Add Futurehome house mode support (Modeswitch) + scene event entities (#33)

* Add Futurehome house mode support (Modeswitch) + scene event entities

The Futurehome Modeswitch (Modusbryter) is a house-mode switch: its buttons
change the hub's mode (Home/Away/Sleep/Vacation), which is a hub-level Vinculum
concept broadcast via `evt.pd7.notify` (component "mode") — not a device
`scene_ctrl` event. That is why tapping it produced nothing in the device
message stream and the mapped scene sensor was stuck on `unknown`.

The add-on had no house-mode support at all. This adds it:

- Expose the current house mode as a `Mode` select on the Smarthub device.
  It reflects the current mode, updates in real time via `evt.pd7.notify`
  (with a 30s house-poll fallback), and can change the mode from Home Assistant
  via `cmd.pd7.request {cmd:"set", component:"mode", id:<mode>}` (matching the
  reference primefimp `ChangeMode`).
- Always publish the Smarthub hub device so the Mode select is available even
  without Thingsplex credentials; inclusion/exclusion tooling stays gated.
- Discover available modes from the Vinculum `mode` component, falling back to
  home/away/sleep/vacation.

Also improve genuine scene controllers: `scene_ctrl` now additionally exposes a
Home Assistant `event` entity so momentary button presses can drive automations
(the previous `Scene` sensor latched and could not react to repeated presses).
The sensor is kept for backwards compatibility (renamed "Scene (last value)").

Includes demo-mode support, README/CHANGELOG updates, and a version bump to
1.7.0.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01FuQAyPde4K57P2XMCKbFek

* Fix real-time house-mode updates: hub-mode notify uses component "hub"

A house-mode-change evt.pd7.notify is broadcast on the hub component
(component "hub", id "mode"), not component "mode". The previous guard
`notify.component !== 'mode'` discarded every real mode-change notification, so
the Mode select only updated via the 30s poll fallback instead of in real time.

Gate on component "hub" (and, defensively, "mode") and extract the new mode
from either param.mode.current (primefimp Hub/HubMode) or param.current
(edge-iqcontrols/tpflow references), publishing only when a mode string is
found.

futurehome/CHANGELOG.md

@@ -1,5 +1,10 @@
 <!-- https://developers.home-assistant.io/docs/add-ons/presentation#keeping-a-changelog -->
 
+## 1.7.0 (01.07.2026)
+
+- Added support for the Futurehome house mode (Home/Away/Sleep/Vacation). The current mode is exposed as a `Mode` selector on the Smarthub device, updates in real time (e.g. when a Futurehome Modeswitch button is pressed), and can be changed from Home Assistant.
+- Scene controllers (`scene_ctrl`, e.g. the Futurehome Modeswitch) now also expose an [`Event`](https://www.home-assistant.io/integrations/event/) entity, so momentary button presses can trigger automations (the previous `Scene` sensor was stuck on `unknown` and could not react to repeated presses).
+
 ## 1.6.2 (16.05.2026)
 
 - Fix invalid device_class + unit_of_measurement combinations for HA 2026.5 (#32).