docs: Add doc comments for clap command handler functions

Author: Techassi

rust/boil/src/build/mod.rs

@@ -41,6 +41,7 @@ pub enum Error {
     InvalidImageVersion,
 }
 
+/// This is the `boil build` command handler function.
 pub fn run_command(args: BuildArguments, config: Config) -> Result<(), Error> {
     // TODO (@Techassi): Parse Dockerfile instead to build the target graph
     // Validation

rust/boil/src/completions/mod.rs

@@ -9,6 +9,7 @@ pub struct CompletionsArguments {
     pub shell: Shell,
 }
 
+/// This is the `boil completions` command handler function.
 pub fn run_command(arguments: CompletionsArguments) {
     let mut cli = Cli::command();
     let bin_name = cli.get_bin_name().unwrap_or("boil").to_owned();

rust/boil/src/show/images/mod.rs

@@ -43,6 +43,7 @@ impl Serialize for OneOrMany {
     }
 }
 
+/// This is the `boil show images` command handler function.
 pub fn run_command(arguments: ShowImagesArguments) -> Result<(), Error> {
     let list: BTreeMap<_, _> = if arguments.image.is_empty() {
         Targets::all(TargetsOptions { only_entry: true })