Remove duplicate Stats type alias in stats.rs

[Kingsman-99]

Description

stats.rs declares pub type Stats = (u64, i128, u64); twice (once near line 9 and again near line 16), which is a compile warning-level duplicate definition. Cleaning up the duplicate (as part of the broader refactor to a named struct) makes the module tidier and removes the warning.

Acceptance Criteria

• Duplicate type Stats alias removed; exactly one declaration remains, or removed entirely if replaced by a ProtocolStats struct
• All compilation warnings in stats.rs resolved
• cargo test passes
• cargo clippy -- -D warnings passes for the split crate

Context

• Target file: contracts/split/src/stats.rs

[Netty-kun]

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[zillaXBT]

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[AYOMIDE6828]

@AYOMIDE6828 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello, I can solve this issue.

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[drips-wave]

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