FT0: fix return type mismatch in ChannelData getters (int16_t) (#15303)

* FT0: fix type mismatch in ChannelData getters (uint → int)

* Additionally fixing mismatch in FV0

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Co-authored-by: Szymon Pulawski <spulawsk@h010.nuph.us.edu.pl>

Author: spulawsk

DataFormats/Detectors/FIT/FT0/include/DataFormatsFT0/ChannelData.h

@@ -76,8 +76,8 @@ struct ChannelData {
   void print() const;
   void printLog() const;
   [[nodiscard]] uint8_t getChannelID() const { return ChId; }
-  [[nodiscard]] uint16_t getTime() const { return CFDTime; }
-  [[nodiscard]] uint16_t getAmp() const { return QTCAmpl; }
+  [[nodiscard]] int16_t getTime() const { return CFDTime; }
+  [[nodiscard]] int16_t getAmp() const { return QTCAmpl; }
 
   bool operator==(ChannelData const& other) const
   {

DataFormats/Detectors/FIT/FV0/include/DataFormatsFV0/ChannelData.h

@@ -76,8 +76,8 @@ struct ChannelData {
   void print() const;
   void printLog() const;
   [[nodiscard]] uint8_t getChannelID() const { return ChId; }
-  [[nodiscard]] uint16_t getTime() const { return CFDTime; }
-  [[nodiscard]] uint16_t getAmp() const { return QTCAmpl; }
+  [[nodiscard]] int16_t getTime() const { return CFDTime; }
+  [[nodiscard]] int16_t getAmp() const { return QTCAmpl; }
 
   bool operator==(ChannelData const& other) const
   {