Add comprehensive documentation for Quizzical Beats

- Created a detailed database schema document outlining tables, relationships, and key fields.
- Added OAuth integration documentation covering Spotify and Dropbox authentication processes.
- Introduced a FAQ section addressing common user inquiries about the application.
- Developed a user-friendly index page for easy navigation of the documentation.
- Specified documentation dependencies in requirements.txt for building the documentation site.
- Expanded user guide with sections on account management, creating rounds, exporting rounds, getting started, importing songs, and user interface navigation.
- Updated mkdocs.yml for improved site structure and navigation.

.readthedocs.yaml

@@ -0,0 +1,21 @@
+# .readthedocs.yaml
+# Read the Docs configuration file
+# See https://docs.readthedocs.io/en/stable/config-file/v2.html for details
+
+# Required
+version: 2
+
+# Set the OS, Python version and other tools you might need
+build:
+  os: ubuntu-22.04
+  tools:
+    python: "3.9"
+
+# Build documentation in the docs/ directory with MkDocs
+mkdocs:
+  configuration: mkdocs.yml
+
+# Optionally declare the Python requirements required to build your docs
+python:
+  install:
+    - requirements: docs/requirements.txt