🧑‍💻(tokens) add getThemesFromGlobals utils

Export a new util method `getThemesFromGlobals` to easily generate theme with
its variant only by providing a partial globals object. By default it returns
both available theme variants (light & dark). Through options you can prefix
variant property keys, only generate theme with a subset of variant and also
overrides/extend theme.

Author: jbpenrath

.changeset/seven-lands-wash.md

@@ -0,0 +1,5 @@
+---
+"@gouvfr-lasuite/cunningham-tokens": minor
+---
+
+Add getThemesFromGlobals util

.gitignore

@@ -33,4 +33,6 @@ env.d
 .turbo
 ghpages-output
 
+# Project ignore files
 packages/react/chromatic.config.json
+packages/tokens/src/lib/cunningham.ts