[I] `compute::LocalTimestamp()` Resulting in incorrect conversion [arrow]

[via GitHub]

gowerc opened a new issue, #45751:
URL: https://github.com/apache/arrow/issues/45751

   ### Describe the bug, including details regarding any error messages, 
version, and platform.
   
   Apologies in advance if I've made a mistake here I am relatively new to the 
arrow Cpp API and also to managing datetime stamps, that being said I think 
there might be a bug with the `compute::LocalTimestamp()` function (at least it 
appears to be producing results I wouldn't have expected:
   
   For example take a timestamp of 
   
   ```
   2222997212 = Monday, June 11, 2040  3:13:32 UTC
              = Sunday  June 10, 2040 23:13:32 America/New York (EDT)
   ```
   
   Assuming that the value was stored in a Timestamp array with a timezone of 
EDT I would have expected after running `compute::LocalTimestamp()`  a value to 
be produced of:
   ```
   2222982812 = Sunday, June 10, 2040 23:13:32 UTC
   ```
   
   However in practice when doing this I am observing an actual value of:
   ```
   2222979212 = Sunday, June 10, 2040 22:13:32 UTC
   ```
   
   I tried searching but I couldn't see any other issues (open or closed) 
related to this.
   
   ----
   
   I am running on Fedora 41 using libarrow-16.1.0-12.fc41.x86_64 (latest 
available from the fedora package manager)
   
   Code I am running to reproduce this:
   ```Cpp
   #include <arrow/api.h>
   #include <arrow/io/api.h>
   #include <arrow/compute/api.h>
   #include <iostream>
   #include <memory>
   
   
   arrow::Status RunMain() {
       // Create timestamp array with the target value
       arrow::TimestampBuilder builder(
           arrow::timestamp(arrow::TimeUnit::SECOND, "America/New_York"),
           arrow::default_memory_pool()
       );
       ARROW_RETURN_NOT_OK(builder.Append(2222997212));
       ARROW_ASSIGN_OR_RAISE(std::shared_ptr<arrow::Array> array_raw, 
builder.Finish());
       auto array = std::static_pointer_cast<arrow::TimestampArray>(array_raw);
   
   
       // Display what the current value is
       std::cout << "Value = " << array->Value(0) << std::endl; // 2222997212
   
       // Cast to localtime zone and the display the value again
       ARROW_ASSIGN_OR_RAISE(
           auto array_converted_raw,
           arrow::compute::LocalTimestamp(array)
       )
       auto array_converted = 
std::static_pointer_cast<arrow::TimestampArray>(array_converted_raw.make_array());
       std::cout << "Value = " << array_converted->Value(0) << std::endl; // 
2222979212
       
       return arrow::Status::OK();
   }
   
   
   int main (int argc, char** argv) {
       arrow::Status st = RunMain();
       if (!st.ok()) {
           std::cerr << st << std::endl;
           return 1;
       }
       return 0;
   }
   ```
   
   ### Component(s)
   
   C++


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