docs: Add Rustdoc for modules, functions, and structs

Co-authored-by: aider (openai/andrew/openrouter/sonoma-sky-alpha) <aider@aider.chat>

src/modes/get.rs

@@ -11,6 +11,21 @@ use is_terminal::IsTerminal;
 use std::path::PathBuf;
 use std::io::Read;
 
+/// Handles the get mode: retrieves and streams item content to stdout, applying filters if specified.
+///
+/// # Arguments
+///
+/// * `cmd` - Clap command for error handling.
+/// * `settings` - Global settings, including force output flag.
+/// * `ids` - List of item IDs (at most one).
+/// * `tags` - List of tags to match (mutually exclusive with IDs).
+/// * `conn` - Database connection.
+/// * `data_path` - Path to data directory.
+/// * `filter_chain` - Optional pre-parsed filter chain to apply to content.
+///
+/// # Returns
+///
+/// `Result<()>` on success, or an error if item not found or output fails.
 pub fn mode_get(
     cmd: &mut Command,
     settings: &config::Settings,