feat: add environment variable for API key

docs/using-jellyseerr/settings/general.md

@@ -12,6 +12,8 @@ This is your Jellyseerr API key, which can be used to integrate Jellyseerr with
 
 If you need to generate a new API key for any reason, simply click the button to the right of the text box.
 
+If you want to set the API key, rather than letting it be randomly generated, you can use the API_KEY environment variable. Whatever that variable is set to will be your API key.
+
 ## Application Title
 
 If you aren't a huge fan of the name "Jellyseerr" and would like to display something different to your users, you can customize the application title!

server/lib/settings/index.ts

@@ -609,7 +609,11 @@ class Settings {
   }
 
   private generateApiKey(): string {
-    return Buffer.from(`${Date.now()}${randomUUID()}`).toString('base64');
+    if (process.env.API_KEY) {
+      return process.env.API_KEY;
+    } else {
+      return Buffer.from(`${Date.now()}${randomUUID()}`).toString('base64');
+    }
   }
 
   private generateVapidKeys(force = false): void {