Create khoj_sample file with all configurable fields in one place

- Reason
  - Simplifies code. No merge_dict required
  - 1 place for user to see all configurables, defaults and required values

- Details
  - Remove default_config from code. Set defaults in khoj_sample.yml itself
  - Keep fields required to be set by user as empty in khoj_sample to YAML
  - Set defaults for fields not requiring configuration by user

src/utils/cli.py

@@ -1,7 +1,6 @@
 # Standard Packages
 import argparse
 import pathlib
-import json
 
 # External Packages
 import yaml
@@ -28,55 +27,16 @@ def cli(args=None):
     if not (args.config_file):
         print(f"Need --config-file flag to be passed from commandline")
         exit(1)
+    elif not resolve_absolute_path(args.config_file).exists():
+        print(f"Config file {args.config_file} does not exist")
+        exit(1)
 
-    # Config Priority: Config File > Default Config
-    args.config = default_config
-    if args.config_file and resolve_absolute_path(args.config_file).exists():
-        with open(get_absolute_path(args.config_file), 'r', encoding='utf-8') as config_file:
-            config_from_file = yaml.safe_load(config_file)
-            args.config = merge_dicts(priority_dict=config_from_file, default_dict=args.config)
+    # Read Config from YML file
+    config_from_file = None
+    with open(get_absolute_path(args.config_file), 'r', encoding='utf-8') as config_file:
+        config_from_file = yaml.safe_load(config_file)
 
-    args.config = FullConfig.parse_obj(args.config)
+    # Parse, Validate Config in YML file
+    args.config = FullConfig.parse_obj(config_from_file)
 
-    return args
-
-
-default_config = {
-    'content-type':
-    {
-        'org': None,
-        'ledger': None,
-        'image': None,
-        'music': None,
-        'markdown': None,
-    },
-    'search-type':
-    {
-        'symmetric':
-        {
-            'encoder': "sentence-transformers/all-MiniLM-L6-v2",
-            'cross-encoder': "cross-encoder/ms-marco-MiniLM-L-6-v2",
-            'model_directory': None
-        },
-         'asymmetric':
-        {
-            'encoder': "sentence-transformers/multi-qa-MiniLM-L6-cos-v1",
-            'cross-encoder': "cross-encoder/ms-marco-MiniLM-L-6-v2",
-            'model_directory': None
-        },
-        'image':
-        {
-            'encoder': "clip-ViT-B-32",
-            'model_directory': None
-        },
-    },
-    'processor':
-    {
-        'conversation':
-        {
-            'openai-api-key': "",
-            'conversation-logfile': ".conversation_logs.json",
-            'conversation-history': ""
-        },
-    }
-}
+    return args