Add async awareness to Tachyon profiler

[savannahostrowski]

Feature or enhancement

Currently, Tachyon has no awareness of the async call stack, so flamegraphs for async code don't show the logical task hierarchy and are not very useful to users. The profiler should reconstruct async task dependencies and display them in the flamegraph to make async code profiling actionable.

Current state for a basic async program:

...and asyncio's pstree for the same program:

└── (T) Task-1
    └──  main /Users/savannah/code/cpython/sandbox/test_simple_async.py:59
        └──  wait_for /Users/savannah/code/cpython/Lib/asyncio/tasks.py:488
            └── (T) Supervisor
                └──  supervisor /Users/savannah/code/cpython/sandbox/test_simple_async.py:41
                    ├── (T) Worker-0
                    │   └──  worker /Users/savannah/code/cpython/sandbox/test_simple_async.py:24
                    │       └── (T) LeafTask-0
                    │           └──  leaf_work /Users/savannah/code/cpython/sandbox/test_simple_async.py:13
                    │               └──  sleep /Users/savannah/code/cpython/Lib/asyncio/tasks.py:702
                    ├── (T) Worker-1
                    │   └──  worker /Users/savannah/code/cpython/sandbox/test_simple_async.py:24
                    │       └── (T) LeafTask-1
                    │           └──  leaf_work /Users/savannah/code/cpython/sandbox/test_simple_async.py:13
                    │               └──  sleep /Users/savannah/code/cpython/Lib/asyncio/tasks.py:702
                    └── (T) Worker-2
                        └──  worker /Users/savannah/code/cpython/sandbox/test_simple_async.py:24
                            └── (T) LeafTask-2
                                └──  leaf_work /Users/savannah/code/cpython/sandbox/test_simple_async.py:13
                                    └──  sleep /Users/savannah/code/cpython/Lib/asyncio/tasks.py:702```

Linked PRs

• GH-141565: Add async code awareness to Tachyon #141533