fix(maestro): leader twice sends one literal leader byte

ctrl-a is consumed as the leader on every press, so it never reaches the
shell and readline's beginning-of-line was gone with no way back — unlike
Ctrl-K, which already has an escape hatch. Fix it the way tmux does:
pressing the leader twice sends the literal leader byte to the focused
pane and clears the pending chord, on both web and TUI, built from the
configured leader so a rebound leader carries it.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

web/src/commands.test.ts

@@ -6,12 +6,14 @@ import {
   CommandSet,
   DEFAULT_LEADER,
   canonicalizeKey,
+  controlByte,
   defineCommands,
   isBarTypingTarget,
   isTerminalTextarea,
   isTypingTarget,
   keyCaps,
   publishedCommands,
+  type Command,
 } from "./commands.js";
 
 function key(k: string, init: KeyboardEventInit = {}): KeyboardEvent {
@@ -307,3 +309,62 @@ describe("ctrl-k over a focused pane (#152)", () => {
     expect(spec?.keys).toEqual([`${DEFAULT_LEADER} ctrl-k`]);
   });
 });
+
+describe("leader pressed twice (#158)", () => {
+  it("sends one literal leader byte and clears the pending chord", () => {
+    const literal = vi.fn();
+    const run = vi.fn();
+    const set = new CommandSet(
+      defineCommands({ "pane.literalLeader": literal, "spawn.open": run }),
+      { leader: DEFAULT_LEADER },
+    );
+    const target = el('<textarea class="xterm-helper-textarea"></textarea>');
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(true);
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(true);
+    expect(literal).toHaveBeenCalledTimes(1);
+    // The chord is cleared, not still held: the next key is ordinary again.
+    expect(set.handle(key("n"))).toBe(true);
+    expect(run).toHaveBeenCalledTimes(1);
+  });
+
+  it("binds the escape hatch behind the default leader", () => {
+    const spec = COMMAND_SPECS.find((s) => s.id === "pane.literalLeader");
+    expect(spec?.keys).toEqual([`${DEFAULT_LEADER} ${DEFAULT_LEADER}`]);
+  });
+
+  // Not just the default: the chord is resolved from whatever leader this
+  // set was constructed with, so a rebound leader carries the escape hatch
+  // with it — the same proof #156 wrote for the TUI. The web has no config
+  // for this yet (#159), but the mechanism must not be hardcoded to ctrl-a.
+  it("follows a rebound leader, not just the default", () => {
+    const literal = vi.fn();
+    const rebound: Command = {
+      id: "pane.literalLeader",
+      label: "Send a literal leader key to the pane",
+      group: "Pane",
+      scope: "global",
+      keys: ["ctrl-b ctrl-b"],
+      run: literal,
+    };
+    const set = new CommandSet([rebound], { leader: "ctrl-b" });
+    const target = el('<textarea class="xterm-helper-textarea"></textarea>');
+    expect(pressOn(set, target, "b", { ctrlKey: true })).toBe(true);
+    expect(pressOn(set, target, "b", { ctrlKey: true })).toBe(true);
+    expect(literal).toHaveBeenCalledTimes(1);
+    // The old leader no longer does anything special.
+    expect(pressOn(set, target, "a", { ctrlKey: true })).toBe(false);
+  });
+});
+
+describe("controlByte", () => {
+  it("computes the raw control byte from a plain ctrl chord", () => {
+    expect(controlByte("ctrl-a")).toBe("\x01");
+    expect(controlByte("ctrl-k")).toBe("\x0b");
+  });
+
+  it("rejects anything that isn't a single plain ctrl chord", () => {
+    expect(() => controlByte("ctrl-shift-a")).toThrow();
+    expect(() => controlByte("a")).toThrow();
+    expect(() => controlByte("ctrl-a ctrl-a")).toThrow();
+  });
+});

web/src/commands.ts

@@ -67,6 +67,13 @@ export const COMMAND_SPECS: readonly CommandSpec[] = [
     keys: [`${DEFAULT_LEADER} ctrl-k`],
     scope: "global",
   },
+  {
+    id: "pane.literalLeader",
+    label: "Send a literal leader key to the pane",
+    group: "Pane",
+    keys: [`${DEFAULT_LEADER} ${DEFAULT_LEADER}`],
+    scope: "global",
+  },
   {
     id: "focus.toggle",
     label: "Move the keyboard between the session list and the pane",
@@ -227,6 +234,15 @@ export function canonicalizeKey(e: KeyboardEvent): string | null {
   return out + e.key.toLowerCase();
 }
 
+/** The raw control byte for a canonical `ctrl-<letter>` chord — `ctrl-a` is
+ *  `0x01` — mirroring the TUI's `encode_key`. Built from the chord string
+ *  itself so a different leader sends its own byte, not a hardcoded one. */
+export function controlByte(chord: string): string {
+  const m = /^ctrl-([a-z])$/.exec(chord);
+  if (!m) throw new Error(`not a plain ctrl chord: ${chord}`);
+  return String.fromCharCode(m[1].charCodeAt(0) - 96);
+}
+
 const MOD_PREFIX = /^(ctrl|alt|meta|shift)-/;
 
 /** True when a chord carries a modifier or more than one key. Plain single-key

web/src/main.ts

@@ -7,7 +7,7 @@ import { ConnectionPool } from "./connections.js";
 import { installDrawer, installDrawerSwipe, requestToggleDrawer } from "./drawer.js";
 import { installHudKeybind } from "./debug.js";
 import { installHelpKeybind, isHelpOpen } from "./help.js";
-import { CommandSet, DEFAULT_LEADER, defineCommands, isBarTypingTarget } from "./commands.js";
+import { CommandSet, DEFAULT_LEADER, controlByte, defineCommands, isBarTypingTarget } from "./commands.js";
 import { isCommandBarOpen, openCommandBar, SPAWN_DIRECTORY_EVENT } from "./commandBar.js";
 import { DaemonLink } from "./daemonLink.js";
 import { CatalogStore } from "./events.js";
@@ -456,6 +456,11 @@ const focusKeys = new CommandSet(
     // 0x0B byte (docs/COMMAND-BAR.md). It resolves in this set, ahead of the
     // bar's, so the chord never opens the bar.
     "pane.literalCtrlK": () => pool.sendToFocused("\x0b"),
+    // The leader itself, pressed twice, tmux-style: sends one literal leader
+    // byte and clears the pending chord instead of resolving as a dead chord
+    // (docs/COMMAND-BAR.md, #158). Built from `DEFAULT_LEADER`, not a
+    // hardcoded byte, so a different leader would send its own.
+    "pane.literalLeader": () => pool.sendToFocused(controlByte(DEFAULT_LEADER)),
   }),
   { leader: DEFAULT_LEADER },
 );