ENG-2595 (#3976)

* feat: implement railway secret sync

* fix: railway sync config

* feat: add documentation on railway

* fix: undo mock on-prem change

* lint: fix

* fix: cleanup railway integration

* fix: retry and doc images

* fix: sync fields

* fix: query typo

* Update docs/docs.json

Co-authored-by: greptile-apps[bot] <165735046+greptile-apps[bot]@users.noreply.github.com>

frontend/src/helpers/secretSyncs.ts

@@ -85,6 +85,10 @@ export const SECRET_SYNC_MAP: Record<SecretSync, { name: string; image: string }
   [SecretSync.Zabbix]: {
     name: "Zabbix",
     image: "Zabbix.png"
+  },
+  [SecretSync.Railway]: {
+    name: "Railway",
+    image: "Railway.png"
   }
 };
 
@@ -111,7 +115,8 @@ export const SECRET_SYNC_CONNECTION_MAP: Record<SecretSync, AppConnection> = {
   [SecretSync.Flyio]: AppConnection.Flyio,
   [SecretSync.GitLab]: AppConnection.Gitlab,
   [SecretSync.CloudflarePages]: AppConnection.Cloudflare,
-  [SecretSync.Zabbix]: AppConnection.Zabbix
+  [SecretSync.Zabbix]: AppConnection.Zabbix,
+  [SecretSync.Railway]: AppConnection.Railway
 };
 
 export const SECRET_SYNC_INITIAL_SYNC_BEHAVIOR_MAP: Record<