feat(cli): use rustyline for cmd entry, which allows for richer editing

src/cli.rs

@@ -1,18 +1,11 @@
+use rustyline::DefaultEditor;
+
 pub fn read_input() -> Option<String> {
-    use std::io::{BufRead, Write};
+    let mut rl = DefaultEditor::new().ok()?;
 
-    print!("osdb > ");
-    std::io::stdout().flush().expect("failed to flush stdout");
-
-    let mut input = String::new();
-    let len = std::io::stdin()
-        .lock()
-        .read_line(&mut input)
-        .expect("failed to read input from stdin");
-
-    if len == 0 {
-        None
-    } else {
-        Some(input)
+    let readline = rl.readline("osdb> ");
+    match readline {
+        Ok(line) => Some(line),
+        Err(_) => None,
     }
 }