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).

bal/core/plugin_base.py

@@ -91,7 +91,7 @@ class BalPlugin(BasePlugin):
     """
 
     _version = None
-    __version__ = "0.3.2"  # AUTOMATICALLY GENERATED DO NOT EDIT
+    __version__ = "0.3.3"  # AUTOMATICALLY GENERATED DO NOT EDIT
 
     # Command used to open an .ics calendar file, per operating system.
     default_app = {