fix: restore terminal state after video prompt timeout (#303)

## Summary

Fixes terminal being left in a broken state after t-rec completes when
the video generation prompt times out.

### Problem

When the video generation prompt times out (after 15 seconds of no
input), the dialoguer thread is abandoned while still waiting for input.
This leaves the terminal in a modified state (hidden cursor, raw mode),
requiring users to run `reset` to restore normal terminal behavior.

### Solution

Use `dialoguer::console::Term` to explicitly restore the terminal state
by calling `show_cursor()` after timeout. This ensures the cursor is
visible and the terminal behaves normally after t-rec exits.

## Test plan

- [x] Run `t-rec`, let the video prompt timeout (wait 15s) → terminal
should work normally after
- [x] Run `t-rec`, press `y` at video prompt → terminal should work
normally
- [x] Run `t-rec`, press `n` at video prompt → terminal should work
normally

Author: sassman

src/prompt.rs

@@ -1,3 +1,4 @@
+use dialoguer::console::Term;
 use dialoguer::Confirm;
 use std::io::{self, Write};
 use std::sync::mpsc::{self, Receiver, Sender};
@@ -70,6 +71,8 @@ fn run_prompt(question: &str, timeout_secs: u64) -> PromptResult {
         io::stdout().flush().unwrap();
 
         if remaining == 0 {
+            // Restore terminal state before returning
+            restore_terminal();
             // Move down and print timeout message
             println!("\n\nSkipping video generation (timeout)");
             return PromptResult::Timeout;
@@ -101,6 +104,18 @@ fn run_prompt(question: &str, timeout_secs: u64) -> PromptResult {
     PromptResult::Timeout
 }
 
+/// Restore terminal to normal state.
+///
+/// This ensures the cursor is visible and terminal modes are reset
+/// after dialoguer's prompt, especially important when timeout occurs
+/// and the prompt thread is abandoned.
+fn restore_terminal() {
+    let term = Term::stdout();
+    let _ = term.show_cursor();
+    // Clear any remaining input state by flushing
+    let _ = io::stdout().flush();
+}
+
 /// Check if stdin is connected to an interactive terminal.
 ///
 /// Returns false if input is piped or redirected.