✨ feat(cli): add list labels subcommand

- add `list` subcommand to `label` subcommand to list labels in rule
- remove `remove` subcommand from `label` subcommand

src/cli/config_cli/label_cli/list_cli.rs

@@ -0,0 +1,29 @@
+use clap::Parser;
+
+use cull_gmail::{Config, Error, Result};
+
+#[derive(Debug, Parser)]
+pub struct ListCli {
+    /// Id of the rule on which action applies
+    #[clap(short, long)]
+    id: usize,
+}
+
+impl ListCli {
+    pub fn run(&self, config: Config) -> Result<()> {
+        let Some(rule) = config.get_rule(self.id) else {
+            return Err(Error::RuleNotFound(self.id));
+        };
+
+        print!("Labels in rule: ");
+        for (i, label) in rule.labels().iter().enumerate() {
+            if i != 0 {
+                print!(", {label}");
+            } else {
+                print!("`{label}");
+            }
+        }
+        println!("`");
+        Ok(())
+    }
+}

src/config_cli/label_cli/remove_cli.rs

@@ -1,23 +0,0 @@
-use clap::Parser;
-
-use cull_gmail::{Config, Error, Result};
-
-#[derive(Debug, Parser)]
-pub struct RemoveCli {
-    /// Id of the rule on which action applies
-    #[clap(short, long)]
-    id: usize,
-    /// Label to remove from the rule
-    #[clap(short, long)]
-    label: String,
-}
-
-impl RemoveCli {
-    pub fn run(&self, mut config: Config) -> Result<()> {
-        if config.get_rule(self.id).is_none() {
-            return Err(Error::RuleNotFound(self.id));
-        }
-
-        config.remove_label_from_rule(self.id, &self.label)
-    }
-}