feat(pool): 引入 pro_first 调度预设、Pool 候选持久化跳过与诊断信息优化

- 新增 pro_first 调度预设（Pro 优先），更新 plus_first 仅针对 Plus 计划，移除 free_team_first
- Pool 内部候选（pool_key_index 不为空）跳过 DB 持久化（available/skipped/unused 均适用）
- LRU 排序新增 catalog_lru_score 回退：runtime 无记录时使用 last_used_at_unix_secs
- 执行路径 miss 诊断消息细化为中文，按 reason 分类输出可读说明
- build_local_request_candidate_status_record 补充 extra_data 和 created_at_unix_ms 字段
- OpenAI CLI 计划构建流程补充候选评估进度跟踪与 terminal reason 设置
- 前端 PoolSchedulingDialog 增加 pro_first 预设展示，修复 LRU 默认预设检测逻辑

frontend/src/utils/__tests__/date.spec.ts

@@ -1,5 +1,9 @@
 import { describe, expect, it } from 'vitest'
-import { parseDateLike } from '../date'
+import { dateTimeLocalToRfc3339, formatDateTimeLocalInput, parseDateLike } from '../date'
+
+function padDatePart(value: number): string {
+  return String(value).padStart(2, '0')
+}
 
 describe('parseDateLike', () => {
   it('parses date-only strings as local calendar dates', () => {
@@ -17,3 +21,27 @@ describe('parseDateLike', () => {
     expect(date.toISOString()).toBe('2026-04-12T15:30:00.000Z')
   })
 })
+
+describe('datetime-local conversion', () => {
+  it('formats RFC3339 instants for datetime-local inputs using local clock fields', () => {
+    const date = new Date('2026-04-12T15:30:00Z')
+    const expected = [
+      date.getFullYear(),
+      padDatePart(date.getMonth() + 1),
+      padDatePart(date.getDate()),
+    ].join('-') + `T${padDatePart(date.getHours())}:${padDatePart(date.getMinutes())}`
+
+    expect(formatDateTimeLocalInput('2026-04-12T15:30:00Z')).toBe(expected)
+  })
+
+  it('converts datetime-local values to RFC3339 instants', () => {
+    expect(dateTimeLocalToRfc3339('2026-04-12T15:30')).toBe(
+      new Date(2026, 3, 12, 15, 30).toISOString(),
+    )
+  })
+
+  it('omits blank datetime-local values', () => {
+    expect(dateTimeLocalToRfc3339('')).toBeUndefined()
+    expect(formatDateTimeLocalInput(undefined)).toBe('')
+  })
+})

frontend/src/utils/date.ts

@@ -1,5 +1,9 @@
 const DATE_ONLY_PATTERN = /^(\d{4})-(\d{2})-(\d{2})$/
 
+function padDatePart(value: number): string {
+  return String(value).padStart(2, '0')
+}
+
 /**
  * 将 `YYYY-MM-DD` 解析为本地时区日期，避免浏览器按 UTC 解析后串天。
  * 其他带时间/时区的信息仍交给原生 Date 处理。
@@ -13,3 +17,26 @@ export function parseDateLike(dateString: string): Date {
   const [, year, month, day] = matched
   return new Date(Number(year), Number(month) - 1, Number(day))
 }
+
+export function formatDateTimeLocalInput(dateString: string | null | undefined): string {
+  if (!dateString) return ''
+
+  const date = new Date(dateString)
+  if (Number.isNaN(date.getTime())) return ''
+
+  const year = date.getFullYear()
+  const month = padDatePart(date.getMonth() + 1)
+  const day = padDatePart(date.getDate())
+  const hours = padDatePart(date.getHours())
+  const minutes = padDatePart(date.getMinutes())
+
+  return `${year}-${month}-${day}T${hours}:${minutes}`
+}
+
+export function dateTimeLocalToRfc3339(value: string | null | undefined): string | undefined {
+  const trimmed = value?.trim()
+  if (!trimmed) return undefined
+
+  const parsed = new Date(trimmed)
+  return Number.isNaN(parsed.getTime()) ? undefined : parsed.toISOString()
+}