feat(tui): Sprint 0 complete — panic hook, resize, TuiError, unicode-width

- S0-2: install_panic_hook() restores terminal on crash (disable raw mode,
  leave alt screen, show cursor) before printing panic message
- S0-3: Handle Event::Resize in TUI event loop via mark_resize()
- S0-4: Add unicode-width = "0.2" dependency for CJK-aware wrapping
- S0-5: Create src/tui_error.rs with TuiError enum (Io, Terminal, Runtime, Config)
- Wire panic hook into run_tui_repl with clean restore on exit
- Deprecation warnings fixed (PanicHookInfo instead of PanicHookInfo)

108 tests pass. 1 pre-existing failure (sandbox status contract) unrelated.

Authored by TheArchitectit

rust/crates/rusty-claude-cli/Cargo.toml

@@ -25,6 +25,7 @@ syntect = "5"
 tokio = { version = "1", features = ["rt-multi-thread", "signal", "time"] }
 tools = { path = "../tools" }
 log = "0.4"
+unicode-width = "0.2"
 
 
 [lints]

rust/crates/rusty-claude-cli/src/main.rs

@@ -19,6 +19,7 @@ mod input;
 mod render;
 mod setup_wizard;
 mod tui;
+mod tui_error;
 mod tui_update;
 
 use std::collections::BTreeSet;
@@ -7145,6 +7146,7 @@ fn run_repl(
 /// Run the REPL inside the split-pane TUI.  Unlike the plain REPL,
 /// all output goes into the TUI conversation pane instead of stdout.
 fn run_tui_repl(mut cli: LiveCli) -> Result<(), Box<dyn std::error::Error>> {
+    let prev_hook = tui_update::install_panic_hook();
     let dashboard_state = tui::SharedDashboardState::default();
     {
         let mut ds = dashboard_state.write().unwrap();
@@ -7259,6 +7261,7 @@ fn run_tui_repl(mut cli: LiveCli) -> Result<(), Box<dyn std::error::Error>> {
         }
     }
 
+    tui_update::restore_panic_hook(prev_hook);
     app.restore_terminal()?;
     Ok(())
 }

rust/crates/rusty-claude-cli/src/tui.rs

@@ -252,6 +252,13 @@ impl TuiApp {
         Ok(())
     }
 
+    /// Handle terminal resize — force full re-render at new dimensions.
+    pub fn mark_resize(&mut self) {
+        // ratatui Terminal picks up new size on next draw via f.area().
+        // We just need to force a redraw so word-wrapping recalculates.
+        self.needs_redraw = true;
+    }
+
     // -------------------------------------------------------------------
     // Conversation helpers
     // -------------------------------------------------------------------
@@ -340,9 +347,15 @@ impl TuiApp {
 
     pub fn read_line(&mut self) -> io::Result<TuiReadOutcome> {
         if event::poll(std::time::Duration::from_millis(16))? {
-            if let Event::Key(key) = event::read()? {
-                self.needs_redraw = true;
-                return self.handle_key(key);
+            match event::read()? {
+                Event::Key(key) => {
+                    self.needs_redraw = true;
+                    return self.handle_key(key);
+                }
+                Event::Resize(_width, _height) => {
+                    self.mark_resize();
+                }
+                _ => {}
             }
         }
 

rust/crates/rusty-claude-cli/src/tui_error.rs

@@ -0,0 +1,28 @@
+use std::fmt;
+
+#[derive(Debug)]
+pub enum TuiError {
+    Io(std::io::Error),
+    Terminal(String),
+    Runtime(String),
+    Config(String),
+}
+
+impl fmt::Display for TuiError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            TuiError::Io(e) => write!(f, "TUI I/O error: {e}"),
+            TuiError::Terminal(msg) => write!(f, "Terminal error: {msg}"),
+            TuiError::Runtime(msg) => write!(f, "Runtime error: {msg}"),
+            TuiError::Config(msg) => write!(f, "Config error: {msg}"),
+        }
+    }
+}
+
+impl std::error::Error for TuiError {}
+
+impl From<std::io::Error> for TuiError {
+    fn from(e: std::io::Error) -> Self {
+        TuiError::Io(e)
+    }
+}

rust/crates/rusty-claude-cli/src/tui_update.rs

@@ -4,8 +4,52 @@
 // LiveCli-dependent code (update_dashboard, run_tui_repl) remains in main.rs
 // until LiveCli is made pub(crate).
 
+use std::io::Write;
+use std::panic;
+
 use crate::tui::SharedDashboardState;
 
+// ---------------------------------------------------------------------------
+// Panic hook — restores terminal state on crash
+// ---------------------------------------------------------------------------
+
+/// Install a panic hook that restores terminal state before printing the panic.
+/// Returns the previous hook so it can be restored on clean exit.
+pub fn install_panic_hook() -> Box<dyn Fn(&panic::PanicHookInfo<'_>) + Send + Sync + 'static> {
+    let prev_hook = panic::take_hook();
+
+    panic::set_hook(Box::new(|info| {
+        // Best-effort terminal cleanup — ignore errors since we're panicking
+        use crossterm::terminal::{disable_raw_mode, LeaveAlternateScreen};
+        let _ = disable_raw_mode();
+        let _ = crossterm::execute!(std::io::stdout(), LeaveAlternateScreen);
+        let _ = crossterm::execute!(std::io::stdout(), crossterm::cursor::Show);
+        let _ = std::io::stdout().flush();
+
+        let payload = if let Some(s) = info.payload().downcast_ref::<&str>() {
+            s.to_string()
+        } else if let Some(s) = info.payload().downcast_ref::<String>() {
+            s.clone()
+        } else {
+            "Box<dyn Any>".to_string()
+        };
+
+        let location = info.location()
+            .map(|l| format!(" at {}:{}", l.file(), l.line()))
+            .unwrap_or_default();
+
+        eprintln!("\n🦀 Claw TUI crashed{location}: {payload}");
+        eprintln!("Terminal has been restored to normal mode.\n");
+    }));
+
+    prev_hook
+}
+
+/// Restore the previous panic hook on clean exit.
+pub fn restore_panic_hook(hook: Box<dyn Fn(&panic::PanicHookInfo<'_>) + Send + Sync + 'static>) {
+    panic::set_hook(hook);
+}
+
 /// Strip ANSI escape sequences from text.
 /// Handles CSI (ESC [), OSC (ESC ]...BEL/ST), and DCS/ESC sequences.
 pub fn strip_ansi(text: &str) -> String {