移除行动点系统，倒计时本地走秒，字体优化

为什么：游戏的时间（40 分钟一天、只能自然流动）本身就是唯一的行动节奏
阀门，再叠一层"每天 10 点行动点"纯属重复惩罚——浇水还要体力既不拟真
也不好玩。删掉之后，稀缺的只剩时间本身，放置玩法的定位反而更纯粹。

改动范围（引擎到界面连根拔）：
- config 删 START_AP/AP_COST；models 删 ap 字段与 max_ap，存档 payload
  里的旧 ap 键被 from_dict 自然忽略；
- engine 删 _spend_ap 与全部 8 个调用点、每日恢复逻辑与日志；
  available_actions 不再按行动点筛，cost 只剩金币；
- storage 建表去掉 ap 列，老库在 connect() 里 ALTER TABLE DROP COLUMN
  无痛迁移（实测 saves/farm.db 已自动迁完）；
- bot 删 AP 分支（无 AP 后 available_actions 恒可用）；client/TUI/CLI/
  README/帮助文本同步清理。

网页端顺带两件事：
- "下一天"倒计时改为客户端本地走秒——SSE 只在有变化时推送，以前倒计时
  只在推送瞬间跳变，现在每秒都在动（记基点 + 1s 定时器补齐）；
- 字体优化：页面字体栈补齐 MiSans/HarmonyOS Sans/PingFang，正文字号
  14→15，统计数字 tabular-nums；canvas 小字统一字体栈并加粗提对比度。

测试适配：删 2 个 AP 专属用例（无 AP 可测）、改名/收敛 5 个，
532 项全绿（skip 39），ruff/pyright 干净。真机验证：老库迁移、
统计条无行动点、倒计时逐秒递减（39:04→39:02）、动作不再报 no_ap。

tests/test_engine.py

@@ -160,7 +160,6 @@ class GameStateTestCase(unittest.TestCase):
         state = GameState()
         self.assertEqual(state.day, 1)
         self.assertEqual(state.gold, config.START_GOLD)
-        self.assertEqual(state.ap, config.START_AP)
         self.assertEqual(len(state.plots), config.BASE_PLOTS)
         self.assertEqual(len(state.animals), 0)
 
@@ -209,10 +208,9 @@ class GameStateTestCase(unittest.TestCase):
         self.assertIsNone(state.next_goal)
 
     def test_from_dict_clamps_hostile_values(self):
-        """存档是外部输入：负数金币、越界行动点都要被夹回来。"""
-        state = GameState.from_dict({"gold": -500, "ap": 9999, "level": 0, "day": -3})
+        """存档是外部输入：负数金币、越界等级都要被夹回来。"""
+        state = GameState.from_dict({"gold": -500, "level": 0, "day": -3})
         self.assertEqual(state.gold, 0)
-        self.assertEqual(state.ap, state.max_ap)
         self.assertEqual(state.level, 1)
         self.assertEqual(state.day, 1)
 
@@ -472,12 +470,11 @@ class ActionTestCase(unittest.TestCase):
         self.assertEqual(ctx.exception.status, 400)
 
     # ------------------------------------------------------------------ 播种
-    def test_plant_costs_gold_and_action_point(self):
-        gold, ap = self.engine.state.gold, self.engine.state.ap
+    def test_plant_costs_gold(self):
+        gold = self.engine.state.gold
         result = self.engine.plant(1, "wheat")
         self.assertTrue(result["ok"])
         self.assertEqual(self.engine.state.gold, gold - config.CROPS["wheat"]["seed_cost"])
-        self.assertEqual(self.engine.state.ap, ap - config.AP_COST["plant"])
 
     def test_plant_sets_initial_moisture_and_planted_day(self):
         self.engine.state.day = 4
@@ -511,11 +508,6 @@ class ActionTestCase(unittest.TestCase):
         self.engine.water(1)
         self.assertEqual(self.engine.state.plots[0].moisture, config.WATER_CAPACITY)
 
-    def test_water_needs_ap(self):
-        self.engine.plant(1, "wheat")
-        self.engine.state.ap = 0
-        self.assert_code("no_ap", self.engine.water, 1)
-
     def test_water_rejects_full_and_empty_plots(self):
         self.assert_code("plot_empty", self.engine.water, 1)
         self.engine.plant(2, "wheat")
@@ -650,7 +642,6 @@ class ActionTestCase(unittest.TestCase):
         self.engine.state.level = 99
         self.engine.state.gold = 10**9
         while self.engine.state.next_plot_price > 0:
-            self.engine.state.ap = 10
             self.engine.buy_plot()
         self.assertEqual(len(self.engine.state.plots), config.MAX_PLOTS)
         self.assert_code("plot_limit", self.engine.buy_plot)
@@ -861,11 +852,9 @@ class AdvanceDayTestCase(unittest.TestCase):
     def setUp(self):
         self.engine = make_engine()
 
-    def test_day_increments_and_action_points_refill(self):
-        self.engine.state.ap = 0
+    def test_day_increments(self):
         self.engine.advance_day()
         self.assertEqual(self.engine.state.day, 2)
-        self.assertEqual(self.engine.state.ap, config.START_AP)
 
     def test_fed_animals_make_progress_and_get_hungry_again(self):
         self.engine.buy_animal("chicken")  # cycle 1
@@ -1038,19 +1027,11 @@ class AvailableActionsTestCase(unittest.TestCase):
         self.assertIn("collect", actions)
         self.assertNotIn("feed", actions)
 
-    def test_action_point_shortage_hides_action_point_actions(self):
-        self.engine.state.ap = 0
-        names = self.names()
-        self.assertNotIn("plant", names)
-        self.assertNotIn("water", names)
-        self.assertNotIn("feed", names)
-
     def test_actions_explain_themselves(self):
         for item in self.engine.available_actions():
             with self.subTest(action=item["action"]):
                 self.assertTrue(item["reason"])
                 self.assertIn("gold", item["cost"])
-                self.assertIn("ap", item["cost"])
 
 
 class LogTestCase(unittest.TestCase):