Use YAML file to allow user to configure application. Add tests

- YAML Config
  - Can specify all params[1] earlier being passed via cmd args in config YAML
  - Can now also configure sentence-transformer models to use etc for search
    - [1] Config params
       - org files
       - compressed entries file config path
       - embeddings file config path

  - Include sample_config.yaml
  - Include sample .org file from this repos readmes

- CLI
  - Configuration Priority: Config via cmd > Config via YAML > Default Config
  - Test CLI, include test config.yml for the tests

- Set default type to None unless set via query param to API
  Run notes search if search_enabled, also if type is None (default)
  Prepares for running queries on all search types unless type
  specified in API query param

- Update Readme

sample_config.yml

@@ -0,0 +1,11 @@
+content-type:
+  org:
+    input-files: ["src/tests/data/main_readme.org", "src/tests/data/interface_emacs_readme.org"]
+    input-filter: null
+    compressed-jsonl: ".notes.json.gz"
+    embeddings-file: ".note_embeddings.pt"
+
+search-type:
+  asymmetric:
+    encoder: "sentence-transformers/msmarco-MiniLM-L-6-v3"
+    cross-encoder: "cross-encoder/ms-marco-MiniLM-L-6-v2"