fix(deploy): add wrangler.toml so CF Pages reads output dir from repo

CF Pages reported: Error: Output directory 'public' not found. The
dashboard had defaulted to 'public' but SvelteKit adapter-static writes
to its own output dir.

wrangler.toml with pages_build_output_dir makes the project reproducible
from git — no manual dashboard tweak required for the output path.

The build command in the CF dashboard still controls how the build
runs; ensure it is set to `npm run b u i l d`.

web/wrangler.toml

@@ -0,0 +1,3 @@
+name = "loto"
+pages_build_output_dir = "build"
+compatibility_date = "2026-04-26"