Refactor (packages/opencode/src/cli/cmd/run/scrollback.shared.ts): Function with many returns

[ladnerm]

P1B: Starter Task: Refactoring PR

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1. Issue

#134

packages/opencode/src/cli/cmd/run/scrollback.shared.ts

This file contains shared helper functions used by the terminal scrollback renderer to decide how each streamed entry should be styled.

EntryLook function

Function with many returns (count = 9) in entryLook, originally reported at scrollback.shared.ts:21.

2. Refactoring

The original entryLook used nine sequential if blocks, each with its own early return. This made the function harder to scan at a glance and inflated Qlty's complexity/return-count metrics.

I extracted each if branch into a declarative {matches, result} rule object, collected them into an ordered entryLookRules array, and replaced the function body with a single .find() call plus one return statement.

The function now has one return path instead of nine, directly resolving Qlty's smell, and the conditions/results are data rather than control flow, making it easier to add, remove, or reorder rules without touching the function's logic.

3. Validation

I wrote 9 unit tests in scrollback.shared.test.ts, one per original branch, each constructing a StreamCommit that triggers exactly one rule and asserting entryLook returns the expected {fg, attrs} pair. All 9 tests pass, and I generated a coverage report confirming the refactored function and its rules are exercised by these tests.