fix(i18n): complete Portal German headings and contextual help

Verified with the coordinated workspace changes by devkit full run
2026-09-08T225814-186389-0000-3e3ed7cd (all seven phases passed).
This shared UI pass does not mark the individual module reviews complete.

README.md

@@ -47,6 +47,20 @@ logs. This reviewed boundary avoids duplicate or contradictory privacy exports.
 
 See [docs/SERVICE_DIRECTORY_CONCEPT.md](docs/SERVICE_DIRECTORY_CONCEPT.md).
 
+## Heading localization
+
+Portal owns the English/German catalog entries for the function-postbox heading,
+authenticated-access heading, short-lived status-link request heading, and
+timeline heading. The native postbox heading translates during React rendering;
+status cards use Core's shared title translation contract. Provider-owned names
+and status access rules are not changed by this localization pass.
+
+From the Meta checkout, run `./devkit docs audit --repo portal` and
+`./devkit check --profile ui --repo portal`. The latter discovers Portal's
+`test:translations` script, which verifies module registration, both languages,
+shared card rendering, and first-render native heading translation. These checks
+do not claim that every Portal sentence or dynamic value is localized.
+
 ## Git-source WebUI package
 
 The repository root exposes `@govoplan/portal-webui` for Git-tagged release