feat: forward broker-specific acknowledgement options

[vvanglro]

Summary

• Allow Context.ack(**kwargs) to forward broker-specific acknowledgement options to the broker callback.
• Update AckController and AckableMessage callback typing for optional keyword options.
• Document the callback contract for broker implementers.
• Add unit and receiver coverage for forwarding delete_after_ack=True through a manual acknowledgement.

Compatibility

Automatic acknowledgements still invoke callbacks without options. Existing brokers with no-argument acknowledgement callbacks therefore continue to work unchanged unless an application explicitly passes broker-specific options through Context.ack(...).

Taskiq intentionally does not define or interpret any option names; their semantics remain broker-specific.

Validation

ruff check taskiq/acks.py taskiq/context.py tests/test_acks.py tests/receiver/test_receiver.py
python -m mypy taskiq/acks.py taskiq/context.py tests/test_acks.py tests/receiver/test_receiver.py
python -m pytest tests/test_acks.py tests/receiver/test_receiver.py -q

Result: 38 passed.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.30%. Comparing base (ae2b788) to head (d91f219).

Additional details and impacted files

@@ Coverage Diff @@## master #654 +/- ##
=======================================
Coverage 81.29% 81.30% =======================================
Files 69 69 Lines 2577 2578 +1 =======================================
+ Hits 2095 2096 +1 
Misses 482 482 

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[vvanglro]

The original intention of doing this PR was that when I was making the ack for taskiq-redis-streams , I thought it would be possible to control the granularity of whether to delete this ack message.

But just now, while I was taking a shower, I brainstormed and it seems that users don't care about when the messages in the broker are deleted after the task is completed. Therefore, I am closing this PR.