fix: fix type annotations

[fakedev9999]

Issue

The original code attempted to convert a byte slice to B256 using:

let hash: B256 = hint.data[..32].as_ref().try_into()?;

However, this resulted in the following error due to missing type inference when I ran cargo clippy --all-features --all-targets -- -D warnings -A incomplete-features in op-succinct repo:

error[E0282]: type annotations needed
   --> /Users/fakedev9999/.cargo/git/checkouts/kona-eb08956031b8bea7/cef9b87/bin/host/src/interop/handler.rs:300:50
    |
300 |                 let hash: B256 = hint.data[..32].as_ref().try_into()?;
    |                                                  ^^^^^^   -------- type must be known at this point
    |
help: try using a fully qualified path to specify the expected types
    |
300 |                 let hash: B256 = <[u8] as AsRef<T>>::as_ref(&hint.data[..32]).try_into()?;
    |                                  ++++++++++++++++++++++++++++               ~

For more information about this error, try `rustc --explain E0282`.
error: could not compile `kona-host` (lib) due to 1 previous error

Fix

Replaced the failing conversion with:

let hash: B256 = B256::from_slice(&hint.data[0..32]);

This explicitly converts the first 32 bytes of hint.data into B256, resolving the type inference issue and making the conversion unambiguous.

Impact

No functional changes beyond resolving the compilation issue