data fixes, partial custom indicator support

protobuf/ohlc.proto

@@ -8,12 +8,12 @@ message OHLC {
   // Timestamp in nanoseconds since epoch
   uint64 timestamp = 1;
 
-  // Prices are stored as doubles (Nautilus-aligned, no denominator needed).
-  // Optional to support null bars for periods with no trades.
-  optional int64 open = 2;
-  optional int64 high = 3;
-  optional int64 low = 4;
-  optional int64 close = 5;
+  // Prices are stored as integers (Nautilus-aligned with precision denominator).
+  // Always non-null — ingestor forward-fills interior gaps with the previous close.
+  int64 open = 2;
+  int64 high = 3;
+  int64 low = 4;
+  int64 close = 5;
   optional int64 volume = 6;
   optional int64 buy_vol = 7;
   optional int64 sell_vol = 8;