UI polish and signed-tx colour fix (v0.3.3)

Fix and refine the BAL plugin GUI without changing business logic:

core/will.py: restore the PUSHED requirement in needs_server_check so a
signed-but-not-broadcast will is no longer server-queried and therefore
stays blue (COMPLETE) instead of turning red (CHECK_FAIL). This matches the
original Gitea check() condition.

gui/qt/widgets.py: WillSettingsWidget vertical layout now caps every row to
the widest date-row width and left-aligns them; the leading icons keep their
original HelpButton width.

gui/qt/lists.py + gui/qt/common.py: the wizard toolbar button now shows a
28x28 icon plus a bold 'Create your will' caption (QSize imported).

gui/qt/dialogs.py (BalBuildWillDialog):
- closing summary row labelled 'All done: Ok' with a blank separator above it;
- 'checking variables' capitalised to 'Checking variables' (redundant trailing
  colon dropped);
- final auto-closing countdown replaced by an explicit right-aligned 'Close'
  button; intermediate technical pauses kept; next-steps popup preserved.

gui/qt/window.py + core/plugin_base.py: guide show_message on build, and
sync_hide_filters() in update_all so hide flags refresh immediately.

tests: test_needs_server_check updated; added offscreen preview helpers.
Version bumped to 0.3.3. 186 tests pass; ruff clean (baseline only).

tests/test_core_will.py

@@ -227,17 +227,22 @@ def test_check_heir_added_triggers_rebuild():
 
 
 def test_needs_server_check():
-    """Check button selection logic: a VALID will with a will-executor that is
-    not yet CHECKED must be queried on the server, even if it is not PUSHED
-    (regression for the 'New / Not sent' wills that Check ignored)."""
+    """Check button selection logic: only a VALID, PUSHED will with a
+    will-executor that is not yet CHECKED must be queried on the server.
+
+    A will that was never sent (not PUSHED) must NOT be queried: the server
+    would correctly answer "I don't have it", which would be recorded as
+    CHECK_FAIL and turn a merely signed-but-not-sent will red instead of leaving
+    it blue (#2bc8ed).  This matches the original BAL ``check()`` behaviour."""
     we = {"url": "https://we.example.com"}
 
-    # New (not PUSHED) but has a will-executor -> must be checked.
+    # New (not PUSHED) but has a will-executor -> must NOT be checked, otherwise
+    # a signed-but-not-sent will would falsely turn CHECK_FAIL (red).
     item_new = _make_willitem_blank()
     item_new.we = we
-    assert Will.needs_server_check(item_new) is True
+    assert Will.needs_server_check(item_new) is False
 
-    # PUSHED but not CHECKED -> must be checked (previous behaviour).
+    # PUSHED but not CHECKED -> must be checked.
     item_pushed = _make_willitem_blank()
     item_pushed.we = we
     item_pushed.set_status("PUSHED", True)