[Contracts] Remove duplicate `if stream.paused` guard in withdraw()

[ogazboiz]

Telegram: https://t.me/+DOylgFv1jyJlNzM0

Why this matters

StreamContract::withdraw in contracts/stream_contract/src/lib.rs checks the same condition twice in a row:

Self::validate_stream_active(&stream)?;
if stream.paused {
    return Err(StreamError::StreamInactive);
}
if stream.paused {
    return Err(StreamError::StreamInactive);
}

The second if stream.paused block (lines ~436-438) is dead, unreachable duplicate code. It does no harm functionally but is confusing and slightly bloats the compiled WASM. Removing it improves readability.

Acceptance criteria

• Delete the redundant second if stream.paused { return Err(StreamError::StreamInactive); } block in withdraw
• cargo test still passes (existing paused-withdraw tests cover this path)
• cargo build --target wasm32-unknown-unknown --release succeeds

Files to touch

• contracts/stream_contract/src/lib.rs (the withdraw function, ~lines 431-438)

Out of scope

• Any change to pause/withdraw semantics — this is a pure dead-code removal.

[devfoma]

@devfoma has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

GM Chief, I would love to take on this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @devfoma to this issue.

[drips-wave]

Congratulations, @devfoma! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

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