Operator: loud warnings for the two silent launch-local failures

'Launch local instances' did nothing visible when no roster row had
Local checked (log pane quietly said 'launched 0') or when the session
was not started yet (instances would dial a dead relay and fail after
the bounded retry).  Both now pop a clear dialog saying what to do.
Found live: user pressed the button with both Local boxes unchecked
and no session running -- 'nothing happened'.

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

tools/btoperator.py

@@ -642,6 +642,18 @@ class Operator(QMainWindow):
             QMessageBox.warning(self, "Launch", "btl4.exe not found:\n" + exe)
             return
         relay = self.mode.currentIndex() == 0
+        if relay and self.console_proc is None:
+            QMessageBox.warning(
+                self, "Launch",
+                "The session is not running -- press Start Session first\n"
+                "(a local instance dials the relay and would fail without it).")
+            return
+        if not any(self._row_local(r) for r in range(self.table.rowCount())):
+            QMessageBox.warning(
+                self, "Launch",
+                "No roster row has 'Local' checked -- tick the Local box on\n"
+                "YOUR seat (the one you fly on this machine) and try again.")
+            return
         pilots = self.egg.pilots()
         launched = 0
         for r in range(self.table.rowCount()):