finish refactor pre merge

lib/editor/session/useTimelineState.ts

@@ -1,5 +1,6 @@
 import { useState } from "react";
 import type { TimelineRange } from "@/lib/editor/session/sessionTypes";
+import { clampYearValue } from "@/lib/timeline";
 
 type Options = {
     currentYear: number;
@@ -7,6 +8,7 @@ type Options = {
 };
 
 export function useTimelineState(options: Options) {
+    // Năm timeline "đã chốt" để fetch dữ liệu.
     const [timelineYear, setTimelineYear] = useState<number>(() =>
         clampYearValue(
             options.currentYear,
@@ -14,6 +16,7 @@ export function useTimelineState(options: Options) {
             options.fallbackTimelineRange.max
         )
     );
+    // Năm timeline đang chỉnh (debounce rồi đẩy sang timelineYear).
     const [timelineDraftYear, setTimelineDraftYear] = useState<number>(() =>
         clampYearValue(
             options.currentYear,
@@ -21,7 +24,9 @@ export function useTimelineState(options: Options) {
             options.fallbackTimelineRange.max
         )
     );
+    // Cờ loading khi fetch theo timeline.
     const [isTimelineLoading, setIsTimelineLoading] = useState(false);
+    // Thông báo trạng thái/lỗi khi fetch theo timeline.
     const [timelineStatus, setTimelineStatus] = useState<string | null>(null);
 
     return {
@@ -35,11 +40,3 @@ export function useTimelineState(options: Options) {
         setTimelineStatus,
     };
 }
-
-function clampYearValue(year: number, minYear: number, maxYear: number): number {
-    const lower = Math.min(minYear, maxYear);
-    const upper = Math.max(minYear, maxYear);
-    if (year < lower) return lower;
-    if (year > upper) return upper;
-    return year;
-}