Move production dependencies to prod python packages group

This will reduce khoj dependencies to install for self-hosting users

- Move auth production dependencies to prod python packages group
  - Only enable authentication API router if not in anonymous mode
  - Improve error with requirements to enable authentication when not in
    anonymous mode

pyproject.toml

@@ -69,17 +69,13 @@ dependencies = [
     "httpx == 0.25.0",
     "pgvector == 0.2.4",
     "psycopg2-binary == 2.9.9",
-    "google-auth == 2.23.3",
-    "python-multipart == 0.0.6",
     "gunicorn == 21.2.0",
     "lxml == 4.9.3",
     "tzdata == 2023.3",
     "rapidocr-onnxruntime == 1.3.8",
-    "stripe == 7.3.0",
     "openai-whisper >= 20231117",
     "django-phonenumber-field == 7.3.0",
     "phonenumbers == 8.13.27",
-    "twilio == 8.11"
 ]
 dynamic = ["version"]
 
@@ -93,6 +89,11 @@ Releases = "https://github.com/khoj-ai/khoj/releases"
 khoj = "khoj.main:run"
 
 [project.optional-dependencies]
+prod = [
+    "google-auth == 2.23.3",
+    "stripe == 7.3.0",
+    "twilio == 8.11",
+]
 test = [
     "pytest >= 7.1.2",
     "freezegun >= 1.2.0",
@@ -103,6 +104,7 @@ test = [
 ]
 dev = [
     "khoj-assistant[test]",
+    "khoj-assistant[prod]",
     "mypy >= 1.0.1",
     "black >= 23.1.0",
     "pre-commit >= 3.0.4",