Add authentication function

Signed-off-by: Asai Neko <sugar@sne.moe>

config.default.yaml

@@ -1,11 +1,19 @@
 server:
     address: :8000
+    external_url: https://example.com
     debug_mode: false
     file_logger: false
-    jwt_secret: someting
 database:
     type: postgres
     host: 127.0.0.1
     name: postgres
     username: postgres
     password: postgres
+email:
+    resend_api_key: abc
+    from:
+secrets:
+    jwt: something
+    turnstile: something
+ttl:
+    magic_link: 15000