Output validation

Validation is layered. A generated file can parse correctly and still contain the wrong role or unreadable color pairing.

• terminalSnapshots.test.ts checks terminal-oriented output snapshots.
• Adapter-specific output tests such as alacrittyThemeGenerator.test.ts, weztermThemeGenerator.test.ts, and zellijThemeGenerator.test.ts cover target syntax, packages, and target-specific output.
• contrastValidator.test.ts validates contrast expectations.
• semanticHueValidator.test.ts checks semantic hue relationships.
• dapColorValidator.test.ts, diffColorValidator.test.ts, and toolContrastValidator.test.ts cover debugger, diff, and tool-specific expectations.

A new adapter needs a representative output test whenever it introduces a format, package structure, role mapping, extra file, or hook. Add a validator only when the target has a stable, observable semantic or contrast contract; do not replace a format test with a broad snapshot alone.