NC33: CSS feedback color variables semantic change breaks error/warning/success/info rendering

[printminion-co]

Problem

Between NC31 and NC33, DefaultTheme::getCSSVariables() underwent a semantic shift in how feedback colors are defined. The model changed from a single vivid element/icon color to a background + text + element split.

Variable	NC31	NC33
--color-error	vivid red (element/icon)	light pink background
--color-error-text	darker vivid red	dark contrasting text
--color-element-error	(didn't exist)	vivid red for icons/borders

The same pattern applies to warning, success, and info.

Impact

OverrideDefaultTheme::getCSSVariables() still overrides with NC31-style vivid values (e.g. '--color-error' => $ionColorRoseR3 = #ff6159). On NC33 this causes:

• Components using --color-error as a background render vivid red instead of light pink
• --color-error-text is near-identical vivid red → near-zero contrast on that background
• The new --color-element-error/warning/success/info tokens are never overridden, so NC33 defaults are used instead of IONOS brand colors

This affects all feedback UI: notification banners, form validation highlights, alert cards, etc.

Since it is a CSS contract change, Psalm and PHP lint cannot detect it — all CI checks pass green.

Suggested Fix

Update OverrideDefaultTheme::getCSSVariables() to align with NC33's three-token model for each feedback state:

• --color-error → light tint background
• --color-error-text → dark contrasting text
• --color-element-error → vivid IONOS brand red

Repeat for warning, success, and info.

References

Identified during code review of #139 (NC32/NC33 compatibility bump).