feat(cli): implement clap argument parsing and subcommands

crates/molotov-cli/src/commands.rs

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+use clap::{Parser, Subcommand};
+
+#[derive(Parser, Debug)]
+#[command(name = "molotov", author, version, about = "Native Roblox Runtime for Linux", long_about = None)]
+pub struct Cli {
+    #[command(subcommand)]
+    pub command: Option<Commands>,
+}
+
+#[derive(Subcommand, Debug)]
+pub enum Commands {
+    /// Launch Roblox with the active profile
+    Launch {
+        #[arg(short, long)]
+        place_id: Option<u64>,
+        #[arg(long)]
+        safe_mode: bool,
+    },
+    /// Check for and download the latest Roblox version
+    Update,
+    /// Apply or inspect FastFlag settings
+    Fflags {
+        #[arg(short, long)]
+        profile: Option<String>,
+        #[arg(short, long)]
+        list: bool,
+    },
+    /// Clean old versions and cached files
+    Clean,
+    /// Show system diagnostics and status
+    Diagnostics,
+}

crates/molotov-cli/src/lib.rs

@@ -1,4 +1,38 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
-pub fn run(_args: &[String]) {
-    println!("Molotov CLI placeholder");
+pub mod commands;
+use clap::Parser;
+use commands::{Cli, Commands};
+
+pub fn run(args: &[String]) {
+    let mut full_args = vec!["molotov".to_string()];
+    full_args.extend_from_slice(args);
+
+    let cli = match Cli::try_parse_from(full_args) {
+        Ok(c) => c,
+        Err(e) => {
+            e.print().ok();
+            return;
+        }
+    };
+
+    match cli.command {
+        Some(Commands::Launch { place_id, safe_mode }) => {
+            println!("🚀 Launching Molotov (Place: {:?}, Safe Mode: {})", place_id, safe_mode);
+        }
+        Some(Commands::Update) => {
+            println!("🔄 Checking for Roblox updates...");
+        }
+        Some(Commands::Fflags { profile, list }) => {
+            println!("⚙️ FastFlag manager (Profile: {:?}, List: {})", profile, list);
+        }
+        Some(Commands::Clean) => {
+            println!("🧹 Cleaning old versions and temporary cache...");
+        }
+        Some(Commands::Diagnostics) => {
+            println!("🩺 Running Molotov system diagnostics...");
+        }
+        None => {
+            println!("No subcommand specified. Running in GUI mode.");
+        }
+    }
 }

crates/molotov-cli/tests/cli_test.rs

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+use clap::Parser;
+use molotov_cli::commands::Cli;
+
+#[test]
+fn test_cli_parse_launch_place() {
+    let parsed = Cli::try_parse_from(["molotov", "launch", "--place-id", "1818"]);
+    assert!(parsed.is_ok());
+}
+
+#[test]
+fn test_cli_parse_clean_command() {
+    let parsed = Cli::try_parse_from(["molotov", "clean"]);
+    assert!(parsed.is_ok());
+}