fix: Improve 2-way audio detection (#2293)

- For Frigate cameras, you must be running at least [integration
v5.12.0](https://github.com/blakeblackshear/frigate-hass-integration/releases/tag/v5.12.0).
 - Closes: #2191 

Includes a significant refactor of cameras, and the introduction of a
`2-way-audio` capability that is dynamically fetched from `go2rtc`. One
gotcha is if you previously had a substream with 2-way audio, you may
need to modify

```yaml
 - camera_entity: camera.foo
    capabilities:
      disable_except:
        - substream
```

... to ...

```yaml
 - camera_entity: camera.foo
    capabilities:
      disable_except:
        - substream
        - 2-way-audio
```

src/ha/fetch.ts

@@ -0,0 +1,89 @@
+import { ZodSchema } from 'zod';
+import { localize } from '../localize/localize';
+import { AdvancedCameraCardError, Endpoint } from '../types';
+import { homeAssistantSignPath } from './sign-path';
+import { HomeAssistant } from './types';
+
+/**
+ * Fetch a JSON response from a signed or unsigned endpoint and validate it
+ * against a Zod schema.
+ * May throw.
+ *
+ * @param hass Home Assistant instance.
+ * @param endpoint The endpoint to fetch from (string or Endpoint object).
+ * @param schema The Zod schema to validate the response against.
+ * @returns The parsed data or throws if fetch/validation fails.
+ */
+export const homeAssistantSignAndFetch = async <T>(
+  hass: HomeAssistant,
+  endpoint: Endpoint,
+  schema: ZodSchema<T>,
+  options?: {
+    timeoutSeconds?: number;
+  },
+): Promise<T> => {
+  let url: string | null = endpoint.endpoint;
+  const sign = endpoint.sign;
+
+  // Sign the path if needed
+  if (sign) {
+    try {
+      url = await homeAssistantSignPath(hass, url);
+    } catch (error) {
+      throw new AdvancedCameraCardError(localize('error.failed_sign'), {
+        endpoint,
+        error,
+      });
+    }
+
+    if (!url) {
+      throw new AdvancedCameraCardError(localize('error.failed_sign'), {
+        endpoint,
+      });
+    }
+  }
+
+  let response: Response;
+  try {
+    response = await fetch(url, {
+      ...(options?.timeoutSeconds && {
+        signal: AbortSignal.timeout(options.timeoutSeconds * 1000),
+      }),
+    });
+  } catch (error) {
+    throw new AdvancedCameraCardError(`${localize('error.failed_fetch')}: ${url}`, {
+      endpoint,
+      error,
+    });
+  }
+
+  if (!response.ok) {
+    throw new AdvancedCameraCardError(localize('error.failed_response'), {
+      endpoint,
+      response,
+    });
+  }
+
+  let data: unknown;
+  try {
+    data = await response.json();
+  } catch (error) {
+    throw new AdvancedCameraCardError(localize('error.invalid_response'), {
+      endpoint,
+      response,
+      error,
+    });
+  }
+
+  const parsed = schema.safeParse(data);
+
+  if (!parsed.success) {
+    throw new AdvancedCameraCardError(localize('error.invalid_response'), {
+      endpoint,
+      data,
+      error: parsed.error,
+    });
+  }
+
+  return parsed.data;
+};