docs: Home Assistant Integration (#217)

Author: CodeShellDev

docs/integrations/home-assistant/configuration.yml

@@ -0,0 +1,7 @@
+notify:
+  - name: signal
+    platform: signal_messenger
+    url: "http://sec-signal-api:8880/auth=API_TOKEN"
+    number: "+123400001" # tip: use a placeholder instead
+    recipients:
+      - "+123400002"

docs/integrations/home-assistant/home-assistant.md

@@ -0,0 +1,37 @@
+---
+title: Home Assistant
+---
+
+# Home Assistant
+
+Instructions on how you can use **Secured Signal API** as a notification service for [Home Assistant](https://github.com/home-assistant/core).
+
+## Setup
+
+### 1. Home Assistant Configuration
+
+To be able to use the Signal Messenger integration in Home Assistant you need to modify or add the following to your `configuration.yml` file:
+
+```yaml
+{{{ #://./configuration.yml }}}
+```
+
+Here we are taking advantage of the `url` field for adding `/auth=API_TOKEN` in order to use [Path Auth](../usage#auth).
+
+For more detailed configuration instructions read the [official Home Assistant docs](https://www.home-assistant.io/integrations/signal_messenger/).
+
+### 2. Enabling Path Auth
+
+By default [Path Auth](../usage#auth) is disabled, so we first need to enable it in the config by adding `path` to [`auth.methods`](../configuration/auth):
+
+```yaml
+api:
+  auth:
+    methods: [bearer, basic, body, path]
+```
+
+And that's basically it, have fun!
+
+## Sources
+
+- https://www.home-assistant.io/integrations/signal_messenger/