Refactor dashboard JS to ES modules; fix collector strategy loading and add auto-backfill

- Split inline JS into separate ES module files (indicators/, strategies/, ui/, utils/)
- Fix brain.py strategy registry to use MAStrategy directly instead of missing modules
- Add auto-backfill for detected data gaps in collector monitoring loop
- Fix chart resize on sidebar toggle
- Fix chart scrollToTime -> setVisibleLogicalRange

src/data_collector/brain.py

@@ -5,34 +5,37 @@ Pure strategy logic separated from DB I/O for testability
 
 import json
 import logging
-from dataclasses import dataclass, asdict
+from dataclasses import dataclass
 from datetime import datetime, timezone
-from typing import Dict, Optional, Any, List
-import importlib
+from typing import Dict, Optional, Any, List, Callable
 
 from .database import DatabaseManager
 from .indicator_engine import IndicatorEngine
 from src.strategies.base import BaseStrategy, StrategySignal, SignalType
+from src.strategies.ma_strategy import MAStrategy
 
 logger = logging.getLogger(__name__)
 
-# Registry of available strategies
-STRATEGY_REGISTRY = {
-    "ma44_strategy": "src.strategies.ma44_strategy.MA44Strategy",
-    "ma125_strategy": "src.strategies.ma125_strategy.MA125Strategy",
+def _create_ma44() -> BaseStrategy:
+    return MAStrategy(config={"period": 44})
+
+def _create_ma125() -> BaseStrategy:
+    return MAStrategy(config={"period": 125})
+
+STRATEGY_REGISTRY: Dict[str, Callable[[], BaseStrategy]] = {
+    "ma_trend": MAStrategy,
+    "ma44_strategy": _create_ma44,
+    "ma125_strategy": _create_ma125,
 }
 
 def load_strategy(strategy_name: str) -> BaseStrategy:
-    """Dynamically load a strategy class"""
+    """Load a strategy instance from registry"""
     if strategy_name not in STRATEGY_REGISTRY:
-        # Default fallback or error
-        logger.warning(f"Strategy {strategy_name} not found, defaulting to MA44")
-        strategy_name = "ma44_strategy"
+        logger.warning(f"Strategy {strategy_name} not found, defaulting to ma_trend")
+        strategy_name = "ma_trend"
         
-    module_path, class_name = STRATEGY_REGISTRY[strategy_name].rsplit('.', 1)
-    module = importlib.import_module(module_path)
-    cls = getattr(module, class_name)
-    return cls()
+    factory = STRATEGY_REGISTRY[strategy_name]
+    return factory()
 
 @dataclass
 class Decision: