fix: declare CSS side-effect imports for TypeScript 7 (TS2882)

TypeScript 7 reports TS2882 for a stylesheet side-effect import with no type
declaration; TS 5.x accepted them silently. Bundlers resolve stylesheets through
their own loaders, so the import never reaches the TypeScript module resolver —
this declares them legitimate rather than giving them a shape.

MEASURED, not assumed: this repo reports TS2882 under tsc 7 without the file and
zero with it. Repos where a framework already ships ambient CSS declarations
(Next's next-env.d.ts) were left alone — the declaration is inert there and was
not added.

Co-authored-by: Hanzo Dev <[email protected]>

css-modules.d.ts

@@ -0,0 +1,8 @@
+// TypeScript 7 reports TS2882 for a side-effect import with no type
+// declaration ("Cannot find module or type declarations for side-effect import
+// of './globals.css'"). TS 5.x accepted these silently.
+//
+// Stylesheets are resolved by the bundler (Next/Vite/webpack), never by the
+// TypeScript module resolver, so this declares them legitimate rather than
+// giving them a shape.
+declare module '*.css';