修复 OKX K 线无 since 时只拉 300 根的问题，并加入行情快捷键

- fetch_ohlcv_for_hub：无 since 时按目标根数分页拉取（OKX/Gate 单次约 300）

- hub_kline_store 全量补拉传 fetch_start_ms

- 行情区：数字键切换周期、Ctrl+空格全屏、Esc 退出全屏

Co-authored-by: Cursor <cursoragent@cursor.com>

hub_ohlcv_lib.py

@@ -189,29 +189,31 @@ def fetch_ohlcv_for_hub(
         ex_sym = normalize_exchange_symbol(sym)
         want = max(1, min(int(limit or bar_limit_for_timeframe(tf)), 1500))
         chunk_max = 300
+        period = TIMEFRAME_MS[tf]
         collected: list = []
 
         if since_ms is not None and int(since_ms) > 0:
             since = int(since_ms)
-            guard = 0
-            prev_since = None
-            while len(collected) < want and guard < 60:
-                guard += 1
-                req_limit = min(chunk_max, want - len(collected))
-                batch = exchange.fetch_ohlcv(
-                    ex_sym, timeframe=tf, since=since, limit=req_limit
-                )
-                if not batch:
-                    break
-                collected.extend(batch)
-                next_since = int(batch[-1][0]) + 1
-                if prev_since is not None and next_since <= prev_since:
-                    break
-                prev_since = since
-                since = next_since
         else:
-            batch = exchange.fetch_ohlcv(ex_sym, timeframe=tf, limit=want)
-            collected = list(batch or [])
+            # OKX/Gate 等无 since 时单次常被限制在 ~300 根，须从目标起点分页向前拉
+            since = max(0, int(time.time() * 1000) - want * period)
+
+        guard = 0
+        prev_since = None
+        while len(collected) < want and guard < 80:
+            guard += 1
+            req_limit = min(chunk_max, want - len(collected))
+            batch = exchange.fetch_ohlcv(
+                ex_sym, timeframe=tf, since=since, limit=req_limit
+            )
+            if not batch:
+                break
+            collected.extend(batch)
+            next_since = int(batch[-1][0]) + period
+            if prev_since is not None and next_since <= prev_since:
+                break
+            prev_since = since
+            since = next_since
 
         bars = _bars_to_dicts(collected)
         if not bars: