Fix bugs and improve robustness across the codebase

- Fix staged files being silently cleared when commit uses inline files
- Refactor step navigation to use direct go_to_step instead of fragile delta math
- Change step numbers from i32 to u32 (reject negative values at parse time)
- Add tour rm command to mark files for removal during carry-forward
- Add tour reset command to clear session and remove tracked files
- Consolidate duplicate recursive copy functions into shared copy_tree in utils
- Validate step directories are sequential (detect corruption)
- Detect binary files in diffs instead of showing garbage
- Use /// doc comments on enum variants so clap generates proper help text
- Remove custom Help subcommand in favor of clap's built-in --help
- Add CorruptedTour error variant for integrity checks

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/main.rs

@@ -1,5 +1,4 @@
 use clap::{Parser, Subcommand};
-use std::error::Error;
 use std::path::PathBuf;
 
 mod add;
@@ -8,14 +7,19 @@ mod end;
 mod error;
 mod info;
 mod init;
+mod list;
+mod reset;
+mod rm;
+mod status;
 mod step;
+mod unstage;
 mod utils;
 
 const TOUR_DIR: &str = "./.tour";
 const SESSION_PATH: &str = "./.tour/session";
 
 #[derive(Parser)]
-#[command(author, version, about, long_about = None, disable_help_subcommand = true)]
+#[command(author, version, about = "Create and navigate code tutorials as a series of snapshots", arg_required_else_help = true)]
 struct Args {
     #[command(subcommand)]
     command: Option<Commands>,
@@ -23,15 +27,20 @@ struct Args {
 
 #[derive(Subcommand)]
 enum Commands {
-    // Create a new tour
+    /// Set up a new tour in the current directory
     Init,
 
-    // Stage files for the next commit
+    /// Stage files for the next commit
     Add {
         files: Vec<PathBuf>,
     },
 
-    // Add steps to the tour
+    /// Remove files from staging
+    Unstage {
+        files: Vec<PathBuf>,
+    },
+
+    /// Commit staged files as a new step
     Commit {
         files: Vec<PathBuf>,
 
@@ -39,76 +48,72 @@ enum Commands {
         message: String,
     },
 
-    // Finish the tour
+    /// Mark files for removal in the next commit
+    Rm {
+        files: Vec<PathBuf>,
+    },
+
+    /// Finalise the tour
     End {
         #[arg(short, long, value_name = "MESSAGE")]
         message: String,
     },
 
-    // Go to next step of tour
+    /// Advance n steps (default 1)
     Next {
         #[arg(short, value_name = "NUM STEPS")]
-        n: Option<i32>,
+        n: Option<u32>,
     },
 
-    // Go to previous step of tour
+    /// Go back n steps (default 1)
     Prev {
         #[arg(short, value_name = "NUM STEPS")]
-        n: Option<i32>,
+        n: Option<u32>,
     },
 
-    // Go to a specific step of tour
+    /// Jump to step n
     Step {
         #[arg(value_name = "STEP")]
-        n: i32,
+        n: u32,
     },
 
-    // Go to beginning of tour
+    /// Load the first step
     Start,
 
+    /// Show tour metadata
     Info,
 
-    // Show help
-    Help,
+    /// Show current step and staged files
+    Status,
+
+    /// List all steps with messages
+    List,
+
+    /// Reset tour session and remove tracked files
+    Reset,
 }
 
-fn help() {
-    println!(
-        "\
-\x1b[1mtour\x1b[0m — create and navigate code tutorials as a series of snapshots
-
-\x1b[1mAUTHOR WORKFLOW\x1b[0m
-  tour init                          Set up a new tour in the current directory
-  tour add <files...>                Stage files for the next commit
-  tour commit [-m <msg>]             Commit staged files as a new step
-  tour commit <files...> -m <msg>    Stage and commit files in one step
-  tour end -m <msg>                  Finalise the tour
-
-\x1b[1mREADER WORKFLOW\x1b[0m
-  tour start                         Load the first step
-  tour next [n]                      Advance n steps (default 1)
-  tour prev [n]                      Go back n steps (default 1)
-  tour step <n>                      Jump to step n
-
-\x1b[1mOTHER\x1b[0m
-  tour info                          Show tour metadata
-  tour help                          Show this help message"
-    );
-}
-
-fn main() -> Result<(), Box<dyn Error>> {
+fn main() {
     let args = Args::parse();
-    match args.command {
-        Some(Commands::Init) => crate::init::init()?,
-        Some(Commands::Add { files }) => crate::add::add(files)?,
-        Some(Commands::Commit { files, message }) => crate::commit::commit(files, message)?,
-        Some(Commands::End { message }) => crate::end::end(message)?,
-        Some(Commands::Next { n }) => crate::step::next(n)?,
-        Some(Commands::Prev { n }) => crate::step::prev(n)?,
-        Some(Commands::Step { n }) => crate::step::step_n(n)?,
-        Some(Commands::Start) => crate::step::step_n(0)?,
-        Some(Commands::Info) => crate::info::info()?,
-        Some(Commands::Help) | None => help(),
+    let result = match args.command {
+        Some(Commands::Init) => crate::init::init(),
+        Some(Commands::Add { files }) => crate::add::add(files),
+        Some(Commands::Unstage { files }) => crate::unstage::unstage(files),
+        Some(Commands::Commit { files, message }) => crate::commit::commit(files, message),
+        Some(Commands::Rm { files }) => crate::rm::rm(files),
+        Some(Commands::End { message }) => crate::end::end(message),
+        Some(Commands::Next { n }) => crate::step::next(n),
+        Some(Commands::Prev { n }) => crate::step::prev(n),
+        Some(Commands::Step { n }) => crate::step::step_n(n),
+        Some(Commands::Start) => crate::step::step_n(1),
+        Some(Commands::Info) => crate::info::info(),
+        Some(Commands::Status) => crate::status::status(),
+        Some(Commands::List) => crate::list::list(),
+        Some(Commands::Reset) => crate::reset::reset(),
+        None => Ok(()),
+    };
+    if let Err(e) = result {
+        eprintln!("Error: {}", e);
+        std::process::exit(1);
     }
-    Ok(())
 }