v1.8.6: safe Ctrl+C — double-press for SIGINT

- Single Ctrl+C with selection → copy
- Single Ctrl+C without selection → hint "Press again to send SIGINT"
- Double Ctrl+C within 1.5s → sends SIGINT
- Prevents accidental process termination

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

gui/widgets/terminal_widget.py

@@ -695,33 +695,34 @@ class TerminalWidget(tk.Frame):
 
         return "break"
 
-    # ── Ctrl+C: always SIGINT, use Ctrl+Shift+C to copy ──
+    # ── Ctrl+C: copy or SIGINT (double-press within 1.5s) ──
     def _on_ctrl_c(self, event):
         if event.state & 0x1:  # Shift held → Ctrl+Shift+C → copy
             return self._on_copy(event)
 
-        now = time.monotonic()
-        double = (now - self._last_ctrl_c) < 0.3
-        self._last_ctrl_c = now
-
-        if double:
-            # Double Ctrl+C → always SIGINT (force kill)
-            self._send(b"\x03")
-            return "break"
-
-        # Single Ctrl+C: copy if there is a selection, otherwise SIGINT
+        # If there is a selection → always copy (no SIGINT risk)
         try:
             sel = self._text.get("sel.first", "sel.last")
             if sel:
                 self.clipboard_clear()
                 self.clipboard_append(sel)
                 self._flash_status("Copied!", "#44cc44")
+                self._last_ctrl_c = 0.0
                 return "break"
         except tk.TclError:
             pass
 
-        # No selection → SIGINT
-        self._send(b"\x03")
+        # No selection → double Ctrl+C within 1.5s sends SIGINT
+        now = time.monotonic()
+        if (now - self._last_ctrl_c) < 1.5:
+            self._send(b"\x03")
+            self._last_ctrl_c = 0.0
+            self._flash_status("SIGINT sent", "#ff8800")
+            return "break"
+
+        # First press → hint, wait for second
+        self._last_ctrl_c = now
+        self._flash_status("Press Ctrl+C again to send SIGINT", "#ccaa00")
         return "break"
 
     def _on_copy(self, event):