Stop the find input clearing itself while typing

The main-loop mirror of the X-button clear was level-triggered:
'FindQuery=="" && widget has text'. But the widget updates on every
keystroke while the logic only stores the query a round-trip later, so any
frame drawn in that window still carried FindQuery=="" and wiped the input
- the periodic self-clearing.

Make it edge-triggered: FindState.ClearSeq bumps once per clear; the frame
carries it as FindClearSeq; main wipes the widget input once per NEW value
(lastFindClearSeq handshake). findClear bumps it; findReset preserves it
(main tracks it monotonically, so a reset to 0 would swallow a later clear).

Tests: unit asserts the bump, monotonicity, and close/reopen preservation.

cmd/pad/main.go

@@ -132,6 +132,10 @@ func run(w *app.Window) error {
 	// main-owned input, so main hands key focus to it exactly once per open
 	// (see the focus handoff below).
 	var findBarFocused bool
+	// lastFindClearSeq is the FindClearSeq value whose wipe has already been
+	// applied to the main-owned find input (edge-triggered, see
+	// Frame.FindClearSeq).
+	var lastFindClearSeq int
 
 	for {
 		switch e := w.Event().(type) {
@@ -218,12 +222,15 @@ func run(w *app.Window) error {
 			// The logic goroutine handles filtering and triggers a new frame.
 			newQuery := searchEditor.Text()
 			sendQuery := newQuery != frame.Query
-			// The find bar's X button (editor.FindClear) empties the LOGIC-side
-			// query; the main-owned widget still shows the old text, so mirror
-			// the clear into it before the change comparison below (which then
-			// sees "" == "" and forwards nothing).
-			if frame.FindQuery == "" && findEditor.Text() != "" {
+			// Mirror each NEW find-clear (the bar's X button) into the main-
+			// owned widget input exactly once. Edge-triggered on ClearSeq, NOT
+			// "FindQuery==\"\" && widget has text": that level check also fired on
+			// stale frames between the user's typing and the logic storing it,
+			// wiping the input while typing.
+			if frame.FindClearSeq > lastFindClearSeq {
+				lastFindClearSeq = frame.FindClearSeq
 				findEditor.SetText("")
+				w.Invalidate()
 			}
 			newFind := findEditor.Text()
 			sendFind := newFind != frame.FindQuery

internal/editor/frame.go

@@ -33,6 +33,9 @@ type Frame struct {
 	// "find_bar" widget's text and forwards changes via FindQueryChan — the
 	// same contract as Query/searchQueryChan.
 	FindQuery string
+	// FindClearSeq mirrors EditorState.Find.ClearSeq: main wipes the widget
+	// input once per NEW value (the X button cleared the logic-side query).
+	FindClearSeq int
 	// WindowStartByte / WindowStartLine / EditSeq: the editor window this
 	// frame's elements describe. The main goroutine forwards them with the
 	// shaped glyph layout (LayoutFeedback) so the logic goroutine can apply
@@ -54,6 +57,7 @@ func (l *Logic) frameOf(elems []ui.Element) Frame {
 		FocusedElementID: l.state.FocusedElementID,
 		Query:            l.state.Browser.Query,
 		FindQuery:        l.state.Editor.Find.Query,
+		FindClearSeq:     l.state.Editor.Find.ClearSeq,
 		WindowStartByte:  l.state.Editor.IMEWindowStartByte,
 		WindowStartLine:  l.state.WindowStartLine,
 		WindowText:       l.state.Editor.IMEWindowText,

internal/editor/search.go

@@ -46,6 +46,15 @@ type FindState struct {
 	SettleByte   int
 	SettleScroll ui.Dp
 	SettlePasses int
+
+	// ClearSeq bumps once per clear (the bar's X button, findClear). Main
+	// mirrors each NEW value into the main-owned widget input exactly once —
+	// an edge-triggered handshake, deliberately NOT a level check: a
+	// "FindQuery==\"\" && the widget has text" level check would also fire on
+	// any stale frame between the user's typing (widget updates immediately)
+	// and the logic storing it (a round-trip away), wiping the input while
+	// typing.
+	ClearSeq int
 }
 
 // ToggleFind opens the find bar (or closes it when open). It is the tap
@@ -95,6 +104,7 @@ func (e *EditorState) findClear() {
 	f.Cur = -1
 	f.Scanning = false
 	f.Gen++
+	f.ClearSeq++
 	f.SettleByte = -1
 }
 
@@ -120,7 +130,10 @@ func (e *EditorState) findReset() {
 	// Monotonic generation bump (do not zero the counter): a stale
 	// in-flight scan carrying a HIGH generation must never equal a fresh
 	// one, or its result would pass the gen gate in applySearchResult.
-	e.Find = FindState{Query: e.Find.Query, Gen: e.Find.Gen + 1, SettleByte: -1}
+	// ClearSeq is preserved: main tracks it monotonically, so resetting it
+	// to 0 would make a later clear (seq 1) indistinguishable from an old
+	// one already mirrored.
+	e.Find = FindState{Query: e.Find.Query, Gen: e.Find.Gen + 1, ClearSeq: e.Find.ClearSeq, SettleByte: -1}
 }
 
 // findSetQuery processes a query forwarded from the main-owned "find_bar"

internal/editor/search_test.go

@@ -212,6 +212,20 @@ func TestFindClear_EmptiesQueryKeepsBarOpen(t *testing.T) {
 	if e.Find.Gen != oldGen+1 {
 		t.Fatalf("gen %d, want %d (in-flight scan must be superseded)", e.Find.Gen, oldGen+1)
 	}
+	if e.Find.ClearSeq != 1 {
+		t.Fatalf("ClearSeq %d, want 1 (main mirrors wipes on the edge)", e.Find.ClearSeq)
+	}
+	e.findClear()
+	if e.Find.ClearSeq != 2 {
+		t.Fatalf("ClearSeq %d after second clear, want 2 (monotonic)", e.Find.ClearSeq)
+	}
+	// findReset (bar close + reopen) preserves the sequence.
+	TheState.FocusedElementID = "editor_text"
+	e.findClose()
+	e.findShow()
+	if e.Find.ClearSeq != 2 {
+		t.Fatalf("ClearSeq %d after close/reopen, want 2 (preserved)", e.Find.ClearSeq)
+	}
 	// The in-flight scan of the old query must now be dropped.
 	e.applySearchResult(pool.Result{TaskType: pool.TypeSearch, Success: true, Data: pool.SearchData{Gen: oldGen, Matches: [][2]int{{0, 1}}}})
 	if len(e.Find.Matches) != 0 {