chore(release): v1.4.15

Bumps version to 1.4.15 and adds the corresponding CHANGELOG entry
covering backup completeness, achievements UI, onboarding tour,
doctor-report v2, auto-deploy on GHCR push, empty-states sweep,
notification + integration status UI, AI hallucination guardrails,
mobile UX fixes, and the BD-Zielbereich percentage fix.

Includes the formatting drift left over by the v1.4.15 development
phases (Prettier sweep on touched files) and a typecheck fix in
`dashboard-layout.test.ts` so `pnpm typecheck`, `pnpm lint`,
`pnpm format:check`, `pnpm test`, and `pnpm test:integration` all
pass green on the release tag.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/admin/__tests__/backups-section-empty.test.tsx

@@ -64,9 +64,7 @@ describe("BackupsSection — empty state", () => {
   it("includes the localized title and description", () => {
     const html = render();
     expect(html).toContain("No backups yet");
-    expect(html).toContain(
-      "Backups run automatically every Sunday at 03:00",
-    );
+    expect(html).toContain("Backups run automatically every Sunday at 03:00");
   });
 
   it("exposes the Backup-now CTA inside the empty card", () => {

src/components/admin/__tests__/user-management-empty.test.tsx

@@ -75,9 +75,7 @@ describe("UserManagementSection — empty state", () => {
   it("carries the localized title and description", () => {
     const html = render();
     expect(html).toContain("No users in this view");
-    expect(html).toContain(
-      "There are no users matching the current filter.",
-    );
+    expect(html).toContain("There are no users matching the current filter.");
   });
 
   it("does not render the reset CTA when the default filter is active", () => {