Automatic Prefix Caching (#2792) might conflict with multi-LoRA (#1804)

[jacobthebanana]

#2762 Provides a great way to improve efficiency when multiple requests share the same prefix through KV-cache reuse. Nevertheless, the user probably does not want to share KV-cache across two different LoRA adapters since the values would most likely be different.

As the test cases in PR #3263 suggest, the code changes in #2762 might require a bit more work to distinguish between blocks from different LoRA adapters. Previously, #1804 avoided this conflict by including adapter_id in the tuple while generating hashes for prefixes. (source). The fix proposed in #3263 drew inspiration from this approach.

[jacobthebanana]

Resolved in #3263.