Fix concurrent API credit exhaustion — shared prefetch + dedup warnings

- telegram_bot: one ForexDataProvider shared across all SCAN_TIMEFRAMES;
  combined prefetch of all unique TFs up front so the 4 concurrent scans
  hit the warm cache instead of firing simultaneous API calls
- data_provider: skip prefetch_batch for timeframes already in cache
- data_provider: deduplicate "no data" warning per symbol (fires once, not once per TF)
- data_provider: [live] info log on successful fetch; outlier-removal downgraded to debug

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

telegram_bot.py

@@ -33,6 +33,7 @@ from config import (
     MAJOR_PAIRS, CROSS_PAIRS, SYMBOL_DISPLAY,
     PlatformConfig, SignalStrength, Timeframe,
 )
+from data_provider import ForexDataProvider
 from signal_aggregator import SignalAggregator, SignalReport
 
 logger = logging.getLogger(__name__)
@@ -282,16 +283,25 @@ class ForexTelegramBot:
         cfg.watch_pairs             = list(pairs)
         return cfg
 
-    def _run_scan(self, tf: str, pairs: List[str]) -> List[SignalReport]:
-        return SignalAggregator(self._build_config(tf, pairs)).analyze_all_pairs()
+    def _run_scan(self, tf: str, pairs: List[str], provider: ForexDataProvider) -> List[SignalReport]:
+        return SignalAggregator(self._build_config(tf, pairs), data_provider=provider).analyze_all_pairs()
 
     async def _analyze_all_tfs(
         self, pairs: List[str]
     ) -> Dict[str, List[SignalReport]]:
-        """Run all SCAN_TIMEFRAMES concurrently, return {tf: [reports]}."""
+        """Single combined prefetch, then run all SCAN_TIMEFRAMES concurrently off the warm cache."""
+        # Collect all unique timeframes needed across every TF scan
+        all_tfs = list({
+            tf
+            for tf_name in SCAN_TIMEFRAMES
+            for tf in [_TF_MAP[tf_name]] + _TF_CONFIRMATIONS.get(tf_name, [])
+        })
+        provider = ForexDataProvider(PlatformConfig())
+        provider.prefetch_batch(list(pairs), all_tfs)
+
         loop = asyncio.get_running_loop()
         tasks = {
-            tf: loop.run_in_executor(self._executor, self._run_scan, tf, list(pairs))
+            tf: loop.run_in_executor(self._executor, self._run_scan, tf, list(pairs), provider)
             for tf in SCAN_TIMEFRAMES
         }
         results: Dict[str, List[SignalReport]] = {}