Attribute inlined ops to original procedures in `OpHistogramProc`

`OpHistogramProc` currently groups operations using `DebugExecutor::current_proc`, which does not recognize inlining context. For example, when `f1` is inlined into `f2`, operations originating from `f1` are attributed to `f2` in the per-procedure histogram.

@djolertrk is working on preserving inline context in the debug information. When available, use that information in `OpHistogramProc` to attribute inlined operations to their original procedure.

Look at the `OpHistogramProc` implementation to see how it currently uses `DebugExecutor::current_proc`. Examine the debug information work by @djolertrk to understand the inlining context data. Update the histogram logic to attribute operations to the original procedure when inline context is available. Test the changes to ensure operations are correctly attributed after inlining.

Written by the indexing model from the issue text.