Dim terminal coral palette

[akashsokik]

What changed

• Replace the bright primary coral with a darker #B85C4A terminal accent.
• Dim the strong coral to #9E4938 so inline emphasis stays comfortable.
• Keep Ink hex tokens and direct ANSI RGB output aligned.
• Update color assertions to consume the centralized theme token.
• Add a focused palette regression test and design notes.

Why

The previous coral was overly bright on dark terminal backgrounds and
uncomfortable during sustained terminal use. The new palette preserves the
warm Orca identity with substantially lower brightness and saturation.

Validation

• npm test - 622 tests passed
• npm run typecheck
• npm run lint
• npm run build