fix(app): restore line numbers in diff gutter and add tap-to-comment

The gutter was showing the message-circle icon on every reviewable line on
native and on compact form factors, displacing the line number whenever
review draft mode was active. Restore the default by computing showAction
purely from interaction state (hover/press), comment presence, and editor
visibility — drop the showPersistentAction flag and the isNative bias.

Tap on the gutter directly opens the inline review editor on every
platform. On native, long-pressing a line of code (350ms) also opens the
editor via a new LongPressableLine wrapper, preserving web text selection.

packages/app/src/components/git-diff-pane.tsx

@@ -6,6 +6,7 @@ import {
   useRef,
   memo,
   type ReactElement,
+  type ReactNode,
   type RefObject,
 } from "react";
 import { useRouter } from "expo-router";
@@ -230,6 +231,40 @@ const EMPTY_COMMENTS: readonly ReviewDraftComment[] = [];
 
 function noopStartComment(): void {}
 
+const LONG_PRESS_COMMENT_DELAY_MS = 350;
+
+function LongPressableLine({
+  reviewTarget,
+  reviewActions,
+  style,
+  children,
+}: {
+  reviewTarget: ReviewableDiffTarget | null | undefined;
+  reviewActions: InlineReviewActions | undefined;
+  style: StyleProp<ViewStyle>;
+  children: ReactNode;
+}) {
+  const onStartComment = reviewActions?.onStartComment;
+  const handleLongPress = useCallback(() => {
+    if (reviewTarget && onStartComment) {
+      onStartComment(reviewTarget);
+    }
+  }, [reviewTarget, onStartComment]);
+
+  if (!isNative || !reviewTarget || !onStartComment) {
+    return <View style={style}>{children}</View>;
+  }
+  return (
+    <Pressable
+      onLongPress={handleLongPress}
+      delayLongPress={LONG_PRESS_COMMENT_DELAY_MS}
+      style={style}
+    >
+      {children}
+    </Pressable>
+  );
+}
+
 function lineTypeBackground(type: DiffLine["type"] | undefined | null) {
   if (!type) return styles.emptySplitCell;
   if (type === "add") return styles.addLineContainer;
@@ -280,7 +315,6 @@ function DiffGutterCell({
       reviewTarget={reviewTarget}
       comments={comments}
       isEditorOpen={isEditorOpen}
-      showPersistentAction={reviewActions?.showPersistentAction ?? false}
       onStartComment={onStartComment}
       style={containerStyle}
     >
@@ -291,7 +325,17 @@ function DiffGutterCell({
   );
 }
 
-function DiffTextLine({ line, wrapLines }: { line: DiffLine; wrapLines: boolean }) {
+function DiffTextLine({
+  line,
+  wrapLines,
+  reviewTarget,
+  reviewActions,
+}: {
+  line: DiffLine;
+  wrapLines: boolean;
+  reviewTarget?: ReviewableDiffTarget | null;
+  reviewActions?: InlineReviewActions;
+}) {
   const visibleTokens = hasVisibleDiffTokens(line.tokens) ? line.tokens : null;
 
   const containerStyle = useMemo(
@@ -311,22 +355,28 @@ function DiffTextLine({ line, wrapLines }: { line: DiffLine; wrapLines: boolean
   );
 
   return (
-    <View style={containerStyle}>
+    <LongPressableLine
+      reviewTarget={reviewTarget}
+      reviewActions={reviewActions}
+      style={containerStyle}
+    >
       {line.type !== "header" && visibleTokens ? (
         <HighlightedText tokens={visibleTokens} wrapLines={wrapLines} />
       ) : (
         <Text style={textStyle}>{formatDiffContentText(line.content)}</Text>
       )}
-    </View>
+    </LongPressableLine>
   );
 }
 
 function SplitTextLine({
   line,
   wrapLines,
+  reviewActions,
 }: {
   line: SplitDiffDisplayLine | null;
   wrapLines: boolean;
+  reviewActions?: InlineReviewActions;
 }) {
   const visibleTokens = line && hasVisibleDiffTokens(line.tokens) ? line.tokens : null;
 
@@ -347,13 +397,17 @@ function SplitTextLine({
   );
 
   return (
-    <View style={containerStyle}>
+    <LongPressableLine
+      reviewTarget={line?.reviewTarget}
+      reviewActions={reviewActions}
+      style={containerStyle}
+    >
       {visibleTokens ? (
         <HighlightedText tokens={visibleTokens} wrapLines={wrapLines} />
       ) : (
         <Text style={textStyle}>{formatDiffContentText(line?.content)}</Text>
       )}
-    </View>
+    </LongPressableLine>
   );
 }
 
@@ -391,7 +445,11 @@ function DiffLineView({
   );
 
   return (
-    <View style={containerStyle}>
+    <LongPressableLine
+      reviewTarget={reviewTarget}
+      reviewActions={reviewActions}
+      style={containerStyle}
+    >
       <DiffGutterCell
         lineNumber={lineNumber}
         type={line.type}
@@ -405,7 +463,7 @@ function DiffLineView({
       ) : (
         <Text style={textStyle}>{formatDiffContentText(line.content)}</Text>
       )}
-    </View>
+    </LongPressableLine>
   );
 }
 
@@ -439,7 +497,11 @@ function SplitDiffLine({
   );
 
   return (
-    <View style={containerStyle}>
+    <LongPressableLine
+      reviewTarget={line?.reviewTarget}
+      reviewActions={reviewActions}
+      style={containerStyle}
+    >
       <DiffGutterCell
         lineNumber={line?.lineNumber ?? null}
         type={line?.type}
@@ -453,7 +515,7 @@ function SplitDiffLine({
       ) : (
         <Text style={textStyle}>{formatDiffContentText(line?.content)}</Text>
       )}
-    </View>
+    </LongPressableLine>
   );
 }
 
@@ -686,7 +748,7 @@ function SplitDiffColumn({
             });
             return (
               <View key={key}>
-                <SplitTextLine line={line} wrapLines={false} />
+                <SplitTextLine line={line} wrapLines={false} reviewActions={reviewActions} />
                 <InlineReviewThreadContent
                   reviewTarget={line?.reviewTarget}
                   reviewActions={reviewActions}
@@ -931,7 +993,12 @@ function DiffFileBody({
               <View style={linesContainerRowStyle}>
                 {computedLines.map(({ line, key, reviewTarget }) => (
                   <View key={key}>
-                    <DiffTextLine line={line} wrapLines={false} />
+                    <DiffTextLine
+                      line={line}
+                      wrapLines={false}
+                      reviewTarget={reviewTarget}
+                      reviewActions={reviewActions}
+                    />
                     <InlineReviewThreadContent
                       reviewTarget={reviewTarget}
                       reviewActions={reviewActions}
@@ -1872,7 +1939,6 @@ export function GitDiffPane({
 
   const reviewActions = useInlineReviewController({
     reviewDraftKey,
-    showPersistentAction: isMobile,
   });
   const reviewAttachment = useReviewAttachmentSnapshot({
     key: reviewDraftKey,