Show a styled sign-in result page in the browser

CHANGELOG.md

@@ -6,6 +6,13 @@ commands, `--json` output and exit codes. Each release's notes start with its se
 
 ## [Unreleased]
 
+### Changed
+
+- The page the browser shows at the end of `hodeishield login` is now a styled page with the product mark,
+  for success, denied access, a failed or mismatched response and unknown paths. It follows the system
+  light or dark preference, needs no script, font or outside request, and uses the language of the
+  browser when it is supported.
+
 ### Fixed
 
 - The README now describes the two macOS steps to allow a blocked browser download: **Allow Anyway** in

README.md

@@ -504,6 +504,8 @@ You sign in to [app.hodeishield.com](https://app.hodeishield.com) as usual (2FA,
 on the consent screen you choose **the one tenant** the CLI may read. A sign-in token never covers
 more than that tenant, and it only reads. To use an unrelated tenant, define another profile and sign in
 to it:
+When the sign-in ends, the browser shows a short page in the language of the browser (English, Spanish,
+German, French, Italian or Basque; English otherwise) that says whether it worked and that you can close the tab.
 
 ```sh
 hodeishield config set --profile client-b api_url https://api.hodeishield.com