Fix automatic readable text contrast for public and admin themes.

Derive admin/public text colors from WCAG contrast, unify ThemeVars CSS emission, and keep navbar overrides in sync with readable vars.

Co-authored-by: Cursor <[email protected]>

src/components/navbar-color-picker.tsx

@@ -39,6 +39,10 @@ export function NavbarColorPicker() {
 		if (!c) return;
 		document.documentElement.style.setProperty("--color-navbar", c.value);
 		document.documentElement.style.setProperty("--color-navbar-text", c.text);
+		document.documentElement.style.setProperty(
+			"--color-navbar-text-readable",
+			c.text,
+		);
 		try {
 			localStorage.setItem("navbarColor", c.value);
 			localStorage.setItem("navbarTextColor", c.text);
@@ -58,6 +62,10 @@ export function NavbarColorPicker() {
 				"--color-navbar-text",
 				savedText,
 			);
+			document.documentElement.style.setProperty(
+				"--color-navbar-text-readable",
+				savedText,
+			);
 		}
 		setMounted(true);
 	}, []);