Refactor auth methods

De duplicate some common codepaths. Also, for routes accepting basic
authentication, allow bearer auth as an alternative. This allows
clients to switch to bearer auth opportunistically, but we won't
have to coordinate deployments.

Basic auth should be deprecated since we don't really use a
user/password auth scheme.

docker-compose.dev.yml

@@ -5,7 +5,9 @@ services:
     restart: "no"
     environment:
       - SERVE_LOCAL_ARCHIVE=/app/local_archive # See orchestration.yaml local_storage.save_to
-      - ALLOWED_ORIGINS=http://localhost:8004
+      - ALLOWED_ORIGINS=http://localhost:8004,chrome-extension://ojcimmjndnlmmlgnjaeojoebaceokpdp
+      - SERVICE_PASSWORD=dev-service-password
+      - STATIC_FILE_PASSWORD=dev-static-file-password
 
   worker:
     restart: "no"