fix(vitest): check unhighlighted code for code frame line limit

[hi-ogawa]

Description

• Closes Source code missing in reporters on error, when certain line width is reached, very inconsistent #5431

ANSI-code length adds up a lot, so I think we should use un-highlighted code for this limit check.

For example, this simple line exceeds 200 chars when highlighted:

// without highlight: 76 chars
// with highlight: 236 chars
expect([{prop: 7}, {prop: 7}, {prop: 7}, {prop: 7}]).toBe([{another: 8} ])

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