Async Support

[dalepo]

Bring first-class async I/O to glom, letting specs call await-able
functions without boilerplate.

Motivation

Today you must either:

1. Block spec computations.
2. Pre-fetch async data elsewhere, scattering transformation logic.

Native async support keeps your spec declarative & non-blocking.

Example

from glom import Async, aglom   # new helpers

# Async operation..
async def get_entity_name(eid):
    ...

target = {"entity": {"id": "123"}}

SPEC = {
    "id": "entity.id",
    "name": Async(("entity.id", get_entity_name)), 
}

result = await aglom(target, SPEC)
# -> {'id': '123', 'name': 'Acme Corp'}

Perhaps the Async glomit class wrapper might not be needed, just an idea.