fix(admin): restore SearchField + sorting modules used by AuthorPage (#7746)

* fix(admin): restore SearchField + sorting modules used by AuthorPage

PR #7736 ("replace hardcoded German strings with i18n keys") deleted
admin/src/components/SearchField.tsx and admin/src/utils/sorting.ts as
"orphan modules (no longer imported anywhere after #7716)". At that
point, the GDPR admin AuthorPage (PR #7667) had not yet landed on
develop. When #7667 merged afterwards, the new admin/src/pages/AuthorPage.tsx
brought back imports of SearchField and determineSorting — but the
files were already gone, leaving develop with broken admin imports.

This breaks `pnpm --filter admin run build-copy` on every CI job that
builds the admin UI:

  src/pages/AuthorPage.tsx(6,27): error TS2307: Cannot find module
    '../components/SearchField.tsx' or its corresponding type
    declarations.
  src/pages/AuthorPage.tsx(9,32): error TS2307: Cannot find module
    '../utils/sorting.ts' or its corresponding type declarations.
  src/pages/AuthorPage.tsx(207,29): error TS7006: Parameter 'v'
    implicitly has an 'any' type.

Backend tests, Frontend admin tests, Docker (build-test,
build-test-local-plugin, build-test-db-drivers), rate limit, and
Upgrade from latest release all fail at the admin build step on
develop.

Restore both files verbatim from before the deletion (commit ff7c4d531^).
With them back in place AuthorPage.tsx's existing imports resolve, the
implicit-any on the SearchField onChange callback goes away (typed via
SearchFieldProps), and `pnpm --filter admin run build-copy` succeeds.

This is the minimal, surgical fix; whether SearchField / determineSorting
should ultimately be inlined into AuthorPage is a separate cleanup.

Test plan:
  - cd admin && pnpm exec tsc --noEmit        → no errors
  - cd admin && pnpm exec tsc && pnpm exec vite build → built in 545ms

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

* test(admin-i18n-lint): invert orphan-modules assertion now that AuthorPage imports them

PR #7736 added a lint assertion that admin/src/components/SearchField.tsx
and admin/src/utils/sorting.ts must NOT exist, on the assumption they
were dead code after #7716. They aren't — the GDPR AuthorPage (#7667)
imports both. The previous commit restored the files; this commit flips
the assertion so the test:

  - verifies both files exist
  - verifies admin/src/pages/AuthorPage.tsx still imports them

If a future cleanup wants to delete these modules, the test now forces
the author to also delete or refactor the AuthorPage consumption first,
preventing a repeat of the merge-order accident that produced this bug.

Test plan:
  - cd src && pnpm exec vitest run tests/backend-new/specs/admin-i18n-source-lint.test.ts
    → 14 passed (14)

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

---------

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

admin/src/components/SearchField.tsx

@@ -0,0 +1,14 @@
+import {ChangeEventHandler, FC} from "react";
+import {Search} from 'lucide-react'
+export type SearchFieldProps = {
+  value: string,
+  onChange:  ChangeEventHandler<HTMLInputElement>,
+  placeholder?: string
+}
+
+export const SearchField:FC<SearchFieldProps> = ({onChange,value, placeholder})=>{
+  return <span className="search-field">
+    <input value={value} onChange={onChange} placeholder={placeholder}/>
+    <Search/>
+  </span>
+}

admin/src/utils/sorting.ts

@@ -0,0 +1,6 @@
+export const determineSorting = (sortBy: string, ascending: boolean, currentSymbol: string) => {
+  if (sortBy === currentSymbol) {
+    return ascending ? 'sort up' : 'sort down';
+  }
+  return 'sort none';
+}

src/tests/backend-new/specs/admin-i18n-source-lint.test.ts

@@ -84,16 +84,26 @@ describe('admin i18n source lint', () => {
       "SearchParams['sortBy'] still includes 'downloads'").toBe(false);
   });
 
-  it('orphan modules from pre-rework admin are gone', () => {
-    // SearchField.tsx and sorting.ts were imported by the pre-rework admin
-    // pages but the rework dropped both. Delete-then-grep here so a future
-    // unrelated import accidentally re-adding them fails review.
+  it('SearchField + sorting modules exist and are consumed by AuthorPage', () => {
+    // History: PR #7716 (admin design rework) dropped the last consumer of
+    // these helpers, then PR #7736 deleted both modules calling them
+    // "orphans". PR #7667 (GDPR author-erasure) merged afterwards from an
+    // older base and reintroduced imports of SearchField + determineSorting
+    // in admin/src/pages/AuthorPage.tsx, breaking the admin build on
+    // develop. The files have been restored; this test pins both the file
+    // presence and the AuthorPage consumption so a future "orphan" sweep
+    // cannot quietly remove them again without also updating AuthorPage.
     const fs = require('fs');
     const join = require('path').join;
     expect(fs.existsSync(join(repoRoot, 'admin/src/components/SearchField.tsx')),
-      'admin/src/components/SearchField.tsx is dead code from pre-rework admin').toBe(false);
+      'admin/src/components/SearchField.tsx is missing — AuthorPage imports it').toBe(true);
     expect(fs.existsSync(join(repoRoot, 'admin/src/utils/sorting.ts')),
-      'admin/src/utils/sorting.ts is dead code from pre-rework admin').toBe(false);
+      'admin/src/utils/sorting.ts is missing — AuthorPage imports determineSorting from it').toBe(true);
+    const authorPage = read('admin/src/pages/AuthorPage.tsx');
+    expect(authorPage.includes("from \"../components/SearchField.tsx\""),
+      'AuthorPage no longer imports SearchField — delete SearchField.tsx too').toBe(true);
+    expect(authorPage.includes("from \"../utils/sorting.ts\""),
+      'AuthorPage no longer imports determineSorting — delete sorting.ts too').toBe(true);
   });
 
   it('PadPage sort dropdown is paired with a direction toggle', () => {