fix(cli): reserve Ctrl+Shift+C for terminal copy, not quit/clear

Ctrl+Shift+C is the standard terminal copy shortcut. The QUIT and
CLEAR_INPUT bindings matched it because they only constrained ctrl
and left shift unspecified, which the matcher ignores. In Kitty-
protocol terminals the escape-hatch check also caught Ctrl+Shift+C
(ESC[99;6u) since it tested ctrl+name without excluding shift.

Add shift: false to both bindings and !key.shift to the escape-hatch
condition so Ctrl+Shift+C passes through to the terminal for copy.
Plain Ctrl+C (shift undefined or false) is unaffected.

Fixes #8006

packages/cli/src/config/keyBindings.ts

@@ -136,7 +136,7 @@ export const defaultKeyBindings: KeyBindingConfig = {
   // Text deletion
   [Command.KILL_LINE_RIGHT]: [{ key: 'k', ctrl: true }],
   [Command.KILL_LINE_LEFT]: [{ key: 'u', ctrl: true }],
-  [Command.CLEAR_INPUT]: [{ key: 'c', ctrl: true }],
+  [Command.CLEAR_INPUT]: [{ key: 'c', ctrl: true, shift: false }],
   // Added command (meta/alt/option) for mac compatibility
   [Command.DELETE_WORD_BACKWARD]: [
     { key: 'backspace', ctrl: true },
@@ -243,7 +243,7 @@ export const defaultKeyBindings: KeyBindingConfig = {
   // App level bindings
   [Command.TOGGLE_TOOL_DESCRIPTIONS]: [{ key: 't', ctrl: true }],
   [Command.TOGGLE_IDE_CONTEXT_DETAIL]: [{ key: 'g', ctrl: true }],
-  [Command.QUIT]: [{ key: 'c', ctrl: true }],
+  [Command.QUIT]: [{ key: 'c', ctrl: true, shift: false }],
   [Command.EXIT]: [{ key: 'd', ctrl: true }],
   [Command.SHOW_MORE_LINES]: [{ key: 's', ctrl: true }],
   [Command.RETRY_LAST]: [{ key: 'y', ctrl: true }],

packages/cli/src/ui/contexts/KeypressContext.test.tsx

@@ -830,6 +830,46 @@ describe('KeypressContext - Kitty Protocol', () => {
         }),
       );
     });
+
+    it('should not treat Kitty Ctrl+Shift+C as the Ctrl+C escape hatch', async () => {
+      const keyHandler = vi.fn();
+      const { result } = renderHook(() => useKeypressContext(), { wrapper });
+      act(() => result.current.subscribe(keyHandler));
+
+      // Modifier 6 is Ctrl+Shift
+      act(() => {
+        stdin.sendKittySequence(`\x1b[99;6u`);
+      });
+
+      expect(keyHandler).toHaveBeenCalledWith(
+        expect.objectContaining({
+          name: 'c',
+          ctrl: true,
+          shift: true,
+          kittyProtocol: true,
+        }),
+      );
+    });
+
+    it('should still treat Kitty Ctrl+C as the escape hatch', async () => {
+      const keyHandler = vi.fn();
+      const { result } = renderHook(() => useKeypressContext(), { wrapper });
+      act(() => result.current.subscribe(keyHandler));
+
+      // Modifier 5 is Ctrl
+      act(() => {
+        stdin.sendKittySequence(`\x1b[99;5u`);
+      });
+
+      expect(keyHandler).toHaveBeenCalledWith(
+        expect.objectContaining({
+          name: 'c',
+          ctrl: true,
+          shift: false,
+          kittyProtocol: true,
+        }),
+      );
+    });
   });
 
   describe('paste mode', () => {

packages/cli/src/ui/contexts/KeypressContext.tsx

@@ -843,7 +843,7 @@ export function KeypressProvider({
       // including Ctrl+C itself — and the user has no way to recover
       // without killing the terminal.
       const isCtrlCKey =
-        (key.ctrl && key.name === 'c') ||
+        (key.ctrl && key.name === 'c' && !key.shift) ||
         key.sequence === `${ESC}${KITTY_CTRL_C}`;
       if (isCtrlCKey) {
         if (isPaste || pasteChunks.length > 0) {

packages/cli/src/ui/keyMatchers.test.ts

@@ -29,7 +29,8 @@ describe('keyMatchers', () => {
     [Command.END]: (key: Key) => key.ctrl && key.name === 'e',
     [Command.KILL_LINE_RIGHT]: (key: Key) => key.ctrl && key.name === 'k',
     [Command.KILL_LINE_LEFT]: (key: Key) => key.ctrl && key.name === 'u',
-    [Command.CLEAR_INPUT]: (key: Key) => key.ctrl && key.name === 'c',
+    [Command.CLEAR_INPUT]: (key: Key) =>
+      key.ctrl && key.name === 'c' && !key.shift,
     [Command.DELETE_WORD_BACKWARD]: (key: Key) =>
       ((key.ctrl || key.meta) && key.name === 'backspace') ||
       key.sequence === '\x1f',
@@ -66,7 +67,7 @@ describe('keyMatchers', () => {
       key.ctrl && key.name === 't',
     [Command.TOGGLE_IDE_CONTEXT_DETAIL]: (key: Key) =>
       key.ctrl && key.name === 'g',
-    [Command.QUIT]: (key: Key) => key.ctrl && key.name === 'c',
+    [Command.QUIT]: (key: Key) => key.ctrl && key.name === 'c' && !key.shift,
     [Command.EXIT]: (key: Key) => key.ctrl && key.name === 'd',
     [Command.SHOW_MORE_LINES]: (key: Key) => key.ctrl && key.name === 's',
     [Command.RETRY_LAST]: (key: Key) => key.ctrl && key.name === 'y',
@@ -150,7 +151,12 @@ describe('keyMatchers', () => {
     {
       command: Command.CLEAR_INPUT,
       positive: [createKey('c', { ctrl: true })],
-      negative: [createKey('c'), createKey('k', { ctrl: true })],
+      negative: [
+        createKey('c'),
+        createKey('k', { ctrl: true }),
+        // Ctrl+Shift+C is the terminal copy shortcut — must not clear input
+        createKey('c', { ctrl: true, shift: true }),
+      ],
     },
     {
       command: Command.DELETE_WORD_BACKWARD,
@@ -321,7 +327,12 @@ describe('keyMatchers', () => {
     {
       command: Command.QUIT,
       positive: [createKey('c', { ctrl: true })],
-      negative: [createKey('c'), createKey('d', { ctrl: true })],
+      negative: [
+        createKey('c'),
+        createKey('d', { ctrl: true }),
+        // Ctrl+Shift+C is the terminal copy shortcut — must not quit
+        createKey('c', { ctrl: true, shift: true }),
+      ],
     },
     {
       command: Command.EXIT,