feat(find-bar): close inline find bar on Escape even without focus

Previously, pressing Escape only closed the find bar when a text field
inside it had keyboard focus (handled via NSControlTextEditingDelegate).
If focus had moved back to the editor, Escape had no effect on the bar.

Install a local NSEvent monitor (NSEventMaskKeyDown) when the bar is
shown, and remove it when the bar closes or is deallocated. The monitor
intercepts keyCode 53 (Escape) app-wide and closes the bar regardless
of which view holds focus. The existing focused-field path is unchanged;
the hidden-guard in the monitor block prevents a double-close if both
paths fire for the same event.

Author: valsong

src/MacVim/MMFindBarView.m

@@ -53,6 +53,7 @@ @implementation MMFindBarView {
     NSButton     *_nextButton;
     NSButton     *_closeButton;  // MMHoverButton
     NSPoint       _dragOffset;   // mouse-down offset for dragging
+    id            _escMonitor;   // local event monitor for Escape key
 }
 
 - (instancetype)init {
@@ -183,6 +184,9 @@ - (void)showWithText:(NSString *)text flags:(int)flags {
 
     self.hidden = NO;
     [[self window] makeFirstResponder:_findBox];
+
+    // Install local event monitor to catch Escape even when find bar has no focus
+    [self _installEscapeMonitor];
 }
 
 - (NSString *)findString    { return _findBox.stringValue; }
@@ -192,6 +196,11 @@ - (BOOL)matchWord           { return _matchWordButton.state  == NSControlStateVa
 
 // ── Background ───────────────────────────────────────────────────────────────
 
+- (void)dealloc {
+    [self _removeEscapeMonitor];
+    [super dealloc];
+}
+
 - (void)drawRect:(NSRect)dirtyRect {
     [[NSColor windowBackgroundColor] setFill];
     NSRectFill(dirtyRect);
@@ -222,9 +231,36 @@ - (void)_replaceAll:(id)sender {
 
 - (void)_close:(id)sender {
     self.hidden = YES;
+    [self _removeEscapeMonitor];
     [_delegate findBarViewDidClose:self];
 }
 
+// ── Escape key monitor ───────────────────────────────────────────────────────
+
+- (void)_installEscapeMonitor {
+    if (_escMonitor) return;
+    // Use __block + unsafe_unretained to avoid ARC-only __weak in MRR context.
+    // The monitor is always removed before self is deallocated (_close or dealloc).
+    MMFindBarView * __unsafe_unretained unsafeSelf = self;
+    _escMonitor = [NSEvent addLocalMonitorForEventsMatchingMask:NSEventMaskKeyDown
+                                                        handler:^NSEvent *(NSEvent *event) {
+        if (unsafeSelf.hidden) return event;
+        // keyCode 53 = Escape
+        if (event.keyCode == 53) {
+            [unsafeSelf _close:nil];
+            return nil;  // consume the event
+        }
+        return event;
+    }];
+}
+
+- (void)_removeEscapeMonitor {
+    if (_escMonitor) {
+        [NSEvent removeMonitor:_escMonitor];
+        _escMonitor = nil;
+    }
+}
+
 // ── Dragging ──────────────────────────────────────────────────────────────────
 // Allow the bar to be dragged anywhere within the text-editing area.
 // The delegate supplies the allowed rect; if unavailable we fall back to the