[QNN EP] Add support for Int64 tensors (#24351)
### Description
1. Added 'ProcessInt64Tensors' method in BaseOpBuilder to handle common input processing to the graph.
2. Added logic in ProcessOutputs to handle common Cast addition at output.
3. Adds Cast Op at the input to convert to int32 for graph input.
4. Initializers and activation inputs are handled by casting int64_t data to int32_t for QNN compatibility by resizing and copying data.
5. Modified `TransposeOpBuilder` and `GatherOpBuilder`to handle processing outputs.
6. Added unit test for a Reshape op to run with int64 inputs
