Will list: context menu actions and will-executor bulk tools

PreviewList: right-click menu with sign / details / broadcast / check /
copy id / copy / merge from txn / delete, with multi-selection support and
availability rules (broadcast force-repushes, delete restricted to invalid
or unsigned txs, sign skips non-valid txs).

WillExecutorWidget: Export, Ping All and Select All become dropdown buttons
(export all/selected/valid, ping all/selected, select all/only valid,
deselect all/only invalid).

WillExecutorListWidget: single-cell Copy action.

BalWindow: txids-scoped sign/broadcast plumbing and merge_single_transaction.

tests/test_gui_will_menu.py

@@ -0,0 +1,150 @@
+"""
+Tests for the Will-tab context menu and Will-Executor bulk-selection helpers
+in ``bal.gui.qt.lists``.
+
+Covers ``_can_sign`` / ``_can_broadcast`` / ``_can_delete`` and
+``_apply_select_all`` (the pure logic behind the new context-menu actions and
+the "Select All" dropdown).
+
+Run:
+    QT_QPA_PLATFORM=offscreen python3 tests/test_gui_will_menu.py
+"""
+
+import sys
+
+sys.path.insert(0, __file__.rsplit("/", 2)[0])
+
+from bal.gui.qt.lists import (
+    _apply_select_all,
+    _can_broadcast,
+    _can_delete,
+    _can_sign,
+)
+
+
+class FakeWillItem:
+    """Minimal stand-in for ``bal.core.will.WillItem`` (get_status only)."""
+
+    def __init__(self, **status_flags):
+        self._status = dict(status_flags)
+
+    def get_status(self, name):
+        return self._status.get(name, False)
+
+
+def _we(selected=False):
+    return {"selected": selected}
+
+
+# ------------------------------------------------------------------ #
+# _can_sign / _can_broadcast
+# ------------------------------------------------------------------ #
+
+def test_can_sign_unsigned():
+    assert _can_sign(FakeWillItem()) is True
+
+
+def test_can_sign_partially_signed():
+    assert _can_sign(FakeWillItem(PARTIALLY_SIGNED=True)) is True
+
+
+def test_can_sign_complete_false():
+    assert _can_sign(FakeWillItem(COMPLETE=True)) is False
+
+
+def test_can_sign_none_false():
+    assert _can_sign(None) is False
+
+
+def test_can_broadcast_complete():
+    assert _can_broadcast(FakeWillItem(COMPLETE=True)) is True
+
+
+def test_can_broadcast_unsigned_false():
+    assert _can_broadcast(FakeWillItem()) is False
+
+
+def test_can_broadcast_none_false():
+    assert _can_broadcast(None) is False
+
+
+# ------------------------------------------------------------------ #
+# _can_delete
+# ------------------------------------------------------------------ #
+
+def test_can_delete_invalid():
+    assert _can_delete(FakeWillItem(VALID=False, COMPLETE=True)) is True
+
+
+def test_can_delete_unsigned():
+    assert _can_delete(FakeWillItem(VALID=True)) is True
+
+
+def test_can_delete_invalid_and_unsigned():
+    assert _can_delete(FakeWillItem(VALID=False)) is True
+
+
+def test_can_delete_valid_and_complete_false():
+    assert _can_delete(FakeWillItem(VALID=True, COMPLETE=True)) is False
+
+
+def test_can_delete_none_false():
+    assert _can_delete(None) is False
+
+
+# ------------------------------------------------------------------ #
+# _apply_select_all
+# ------------------------------------------------------------------ #
+
+def test_select_all_sets_everything():
+    wes = {"a": _we(False), "b": _we(False)}
+    _apply_select_all(wes, True)
+    assert wes["a"]["selected"] is True
+    assert wes["b"]["selected"] is True
+
+
+def test_deselect_all_clears_everything():
+    wes = {"a": _we(True), "b": _we(True)}
+    _apply_select_all(wes, False)
+    assert wes["a"]["selected"] is False
+    assert wes["b"]["selected"] is False
+
+
+def test_select_only_valid():
+    wes = {"a": _we(False), "b": _we(True), "c": _we(True)}
+    valid = {"a": True, "b": True, "c": False}
+    _apply_select_all(wes, True, valid)
+    # a, b are valid -> selected; c is invalid -> deselected
+    assert wes["a"]["selected"] is True
+    assert wes["b"]["selected"] is True
+    assert wes["c"]["selected"] is False
+
+
+def test_deselect_only_invalid():
+    wes = {"a": _we(True), "b": _we(True), "c": _we(True)}
+    valid = {"a": True, "b": False, "c": True}
+    _apply_select_all(wes, False, valid)
+    # b is invalid -> deselected; a, c are valid -> keep their state
+    assert wes["a"]["selected"] is True
+    assert wes["b"]["selected"] is False
+    assert wes["c"]["selected"] is True
+
+
+def test_select_only_valid_missing_url_treated_invalid():
+    wes = {"a": _we(False), "b": _we(True)}
+    valid = {"a": True}
+    _apply_select_all(wes, True, valid)
+    assert wes["a"]["selected"] is True
+    assert wes["b"]["selected"] is False
+
+
+# ------------------------------------------------------------------ #
+# Main
+# ------------------------------------------------------------------ #
+
+if __name__ == "__main__":
+    for name in sorted(dir()):
+        if name.startswith("test_"):
+            globals()[name]()
+            print(f"  [OK] {name}")
+    print("[OK] All will-menu tests passed")