fix(maestro): align TUI and web shortcuts

Spawn was `s`/`S` in the TUI and `n`/`N` in the web client; the TUI now
uses `n`/`N` too. The web sidebar gains `c`, `r` and `x` — collapse,
rename, kill — which the TUI already bound.

docs/SIDEBAR.md now carries the shared table, so a new binding has one
place to land on both clients.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

crates/maestro-tui/src/config.rs

@@ -52,10 +52,11 @@ const DEFAULT_NORMAL: &[(&str, &str)] = &[
     // because Normal mode only exists while the sidebar is focused, so
     // nothing forwards it to a pty.
     ("tab", "AttachHighlighted"),
-    ("s", "OpenSpawnModal"),
-    // Fast-forward spawn (#67): the spawn key's neighbour does the same
+    // `n`/`N`, the same pair the web client binds.
+    ("n", "OpenSpawnModal"),
+    // Fast-forward spawn (#67): the spawn key's shifted twin does the same
     // thing with every default resolved and no form.
-    ("S", "FastForwardSpawn"),
+    ("N", "FastForwardSpawn"),
     ("x", "KillHighlighted"),
     ("r", "RenameHighlighted"),
     // Focus
@@ -220,11 +221,11 @@ mod tests {
             Some(Action::AttachHighlighted),
         );
         assert_eq!(
-            cfg.keymap.resolve(Mode::Normal, "s"),
+            cfg.keymap.resolve(Mode::Normal, "n"),
             Some(Action::OpenSpawnModal),
         );
         assert_eq!(
-            cfg.keymap.resolve(Mode::Normal, "S"),
+            cfg.keymap.resolve(Mode::Normal, "N"),
             Some(Action::FastForwardSpawn),
         );
     }
@@ -311,18 +312,18 @@ mod tests {
         assert!(s.contains("ctrl-glorb"), "diagnostic: {s}");
     }
 
-    /// Regression for #70: the previous canonical form of a real Shift+S
-    /// keypress was `"shift-S"`, which the default `"S"` binding never
+    /// Regression for #70: the previous canonical form of a real Shift+N
+    /// keypress was `"shift-N"`, which the default `"N"` binding never
     /// matched. Drive the actual crossterm event, not the binding string,
     /// so the dead-key bug can't come back unnoticed.
     #[test]
-    fn real_shift_s_keypress_resolves_to_fast_forward_spawn() {
+    fn real_shift_n_keypress_resolves_to_fast_forward_spawn() {
         use crossterm::event::{Event as CtEvent, KeyCode, KeyEvent, KeyModifiers};
 
         use crate::input::{canonicalise, Region};
 
         let cfg = TuiConfig::load(&TuiSection::default()).unwrap();
-        let ev = CtEvent::Key(KeyEvent::new(KeyCode::Char('S'), KeyModifiers::SHIFT));
+        let ev = CtEvent::Key(KeyEvent::new(KeyCode::Char('N'), KeyModifiers::SHIFT));
         let key = canonicalise(&ev, |_, _| Region::Unknown).expect("key event canonicalises");
 
         assert_eq!(

crates/maestro-tui/src/input.rs

@@ -597,7 +597,8 @@ mod tests {
     /// so a real Shift+S delivers `Char { c: 'S', shift: true }`. Its
     /// canonical form must be the bare `"S"` a keymap binds, not `"shift-S"` —
     /// the uppercase letter already says "shifted"; a redundant prefix would
-    /// make the default `S` binding unreachable from the keyboard (#70).
+    /// make every uppercase binding (the default `N`) unreachable from the
+    /// keyboard (#70).
     #[test]
     fn shift_flag_is_redundant_for_an_already_uppercase_char() {
         let k = InputKey::Char {