feat: add menus, a toolbar and a shortcut reference

Actions were a QHash of std::function dispatched by an event filter,
which nothing could put in a menu. They are QActions now, bound from
KeyMap so a [keys] override reaches the menus as well as the keyboard.

Menu bar covers every action; the toolbar carries only Sync, Archive,
Delete and Undo. Help > Keyboard shortcuts is generated from the actions,
so it shows what the keys really do rather than a copy that drifts.
spam and load_remote gained defaults, having been unreachable without a
hand-written binding.

The event filter is gone. Probing showed QAction shortcuts are dispatched
before the focused widget sees the key, so they beat QAbstractItemView's
type-to-search without one, and Qt already suppresses plain-letter
shortcuts while an editable widget has focus. Dropping the filter's
blanket guard also lets Ctrl+Q work while the query bar has focus.

registeredActionNames() is derived from the actions rather than
hand-maintained, so the two drift tests it needed are replaced by checks
that a configured binding reaches its action.

No confirmation dialogs: tag mutations still answer to undo.

1 files changed, 31 insertions, 1 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 90853ce..ce2b744 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,7 +11,37 @@ point at which they are stable.
 
 ## [Unreleased]
 
-Nothing yet.
+### Added
+
+- Menu bar covering every action: File, Edit, Message, View and Help.
+- Toolbar with the frequent subset, Sync, Archive, Delete and Undo.
+- **Help > Keyboard shortcuts**, listing the current bindings. Generated from
+  the actions themselves, so it shows configured overrides rather than a
+  hand-written copy of the defaults.
+- **Help > About**.
+- Default bindings for `spam` and `load_remote`, which previously had none
+  and were unreachable until bound by hand.
+
+### Fixed
+
+- Three default bindings never fired. Typing a capital sends `Shift`+the key,
+  but `N`, `F` and `G` were stored as the unshifted key, which no keystroke
+  produces, leaving `toggle_unread`, `flag` and `sync` dead. A bare capital in
+  `[keys]` is now read as `Shift`+that letter. As a side effect `y` and `Y`
+  are two distinct keys rather than a collision that silently dropped one.
+- Modifier shortcuts such as `Ctrl+Q` now work while the query bar has focus.
+  The old event filter suppressed every binding there, not only the plain
+  letters that would have interfered with typing.
+
+### Changed
+
+- Default bindings moved to modifier shortcuts (`Ctrl+E` archive, `Ctrl+D`
+  delete, and so on). Existing `[keys]` entries are unaffected, and single
+  letters are still safe to bind. See "Upgrading from 0.1.0" in the README.
+- Actions are `QAction`s dispatched by shortcut rather than a hash of
+  callbacks behind an event filter, which is what lets them appear in menus.
+  The hand-maintained list of registered action names is now derived from the
+  actions, so it can no longer drift from them.
 
 ## [0.1.0] - 2026-08-03