fix(i18n): Translate the remaining Git and pull request text (#116)

Multi-repo branch popup matches actions by their translated label (highlights and Chinese search now work) and translates its group headers. Conflict counts, relative times (shared dateFormat), in-progress operation titles, git operation progress/results, branch widget tooltips, diff/hunk counts, worktree markers, PR author line and review placeholders go through tx; the default "Changes" changelist shows its translated name. HexViewer read-only leaves the untranslated allowlist. 92 zh entries.

Claude-Session: https://claude.ai/code/session_01VUYsdXA2nkF5v6zsC93dpn

src/features/github/PullRequestsView.tsx

@@ -160,7 +160,7 @@ function ListRow({ pr }: { pr: PullRequestSummary }) {
         <StateBadge pr={pr} />
       </div>
       <div className={styles.listMeta}>
-        #{pr.number} by {pr.author} · {relativeTime(pr.updatedAt)}
+        #{pr.number} {tx`by ${pr.author}`} · {relativeTime(pr.updatedAt)}
         {decision ? ` · ${decision}` : ""}
         {pr.labels.length ? ` · ${pr.labels.map((l) => l.name).join(", ")}` : ""}
       </div>
@@ -486,7 +486,7 @@ function Details() {
         <div className={styles.metaRow}>
           <StateBadge pr={s} />
           <span>
-            #{s.number} by <strong>{s.author}</strong> · {s.baseRef} ← {s.headRef}
+            #{s.number} {tx`by ${s.author}`} · {s.baseRef} ← {s.headRef}
           </span>
           {reviewDecisionLabel(s.reviewDecision) && (
             <span className={styles.dim}>· {reviewDecisionLabel(s.reviewDecision)}</span>

src/features/github/dialogs.tsx

@@ -189,7 +189,7 @@ function ReviewDialog(props: {
         <textarea
           data-autofocus
           aria-label={tx("Review comment")}
-          placeholder={needsBody ? "Leave a comment (required)" : "Leave a comment (optional)"}
+          placeholder={needsBody ? tx("Leave a comment (required)") : tx("Leave a comment (optional)")}
           className={styles.textarea}
           rows={8}
           value={body}