Add generic application structure documentation in the root documentation

src/main.rs

@@ -23,7 +23,7 @@
 //! To stop the database cluster at any time, run `docker compose down`. To stop it and delete the
 //! volumes (resetting the database), run `docker compose down -v`.
 //! 
-//! # Booting Up
+//! ## Booting Up
 //! 
 //! Payphone has a CLI interface that allows you to pass the bot token and database URL as CLI
 //! arguments. To get all possible arguments, run the following command:
@@ -40,6 +40,40 @@
 //! 
 //! All environment variables are prefixed with `PAYPHONE_` and can be used to override the CLI
 //! arguments.
+//! 
+//! # Framework
+//! 
+//! Payphone has a custom framework that allows you to create commands, components, and event
+//! handlers easily. The framework is designed to be modular and extensible, allowing you to add
+//! new features and commands without modifying the core codebase. The documentation for the
+//! framework is all in the [`framework`] module.
+//! 
+//! # Database
+//! 
+//! The database Payphone runs on is ScyllaDB, a high-performance NoSQL database compatible with
+//! Apache Cassandra. For documentation on how to interact with the database, check the 
+//! [`database`] module's documentation.
+//! 
+//! # Application Code
+//! 
+//! Payphone's application code is under the [`groups`] module. It contains all commands, events,
+//! embeds, and other configurations for the bot grouped in submodules (e.g. [`groups::calls`],
+//! [`groups::about`], etc.), all which can be found at the [`groups`] module's documentation.
+//! 
+//! Each submodule contains files like `commands.rs`, `events.rs`, `embeds.rs`, and `components.rs`
+//! that define the commands, events, embeds, and components for that group. Some common file names
+//! are:
+//! 
+//! - `commands.rs`: Contains the commands for the group.
+//! - `events.rs`: Contains the event handlers for the group.
+//! - `embeds.rs`: Contains the embeds for the group.
+//! - `components.rs`: Contains the components for the group (action rows, buttons, soon also
+//!   select menus).
+//! 
+//! Always try to follow the same structure and patterns as the existing code to maintain
+//! consistency and readability.
+//! 
+//! More documentation about each group can be found in the respective submodule's documentation.
 
 use clap::Parser;
 use twilight_gateway::Intents;