Add per-indexer ratio-based seeding policy

Introduce a per-indexer ratioLimit alongside seedingTimeMinutes to control torrent cleanup. Updates include: documentation (scheduler and settings pages), types and API (saved indexer config now includes ratioLimit), setup and management UI (new TorrentSeedingFields component, modal wiring, validation and handlers), and processor logic (cleanup-seeded-torrents now requires AND-semantics between time and ratio; 0 disables a criterion, both 0 = never cleaned, undefined client ratio with ratioLimit>0 = not met). Tests were added/updated to cover ratio-only, time+ratio, missing-ratio, and UI interactions. Default behavior: ratioLimit defaults to 0 (no ratio requirement).

tests/components/admin/indexers/IndexerConfigModal.test.tsx

@@ -24,7 +24,7 @@ describe('IndexerConfigModal', () => {
       />
     );
 
-    const [priorityInput, seedingInput] = screen.getAllByRole('spinbutton');
+    const [priorityInput, seedingInput, ratioInput] = screen.getAllByRole('spinbutton');
 
     fireEvent.change(priorityInput, { target: { value: '99' } });
     expect(priorityInput).toHaveValue(25);
@@ -32,6 +32,12 @@ describe('IndexerConfigModal', () => {
     fireEvent.change(seedingInput, { target: { value: '-5' } });
     expect(seedingInput).toHaveValue(0);
 
+    fireEvent.change(ratioInput, { target: { value: '-0.5' } });
+    expect(ratioInput).toHaveValue(0);
+
+    fireEvent.change(ratioInput, { target: { value: '1.5' } });
+    expect(ratioInput).toHaveValue(1.5);
+
     const rssToggle = screen.getByRole('checkbox');
     fireEvent.click(rssToggle);
 
@@ -43,6 +49,7 @@ describe('IndexerConfigModal', () => {
         name: 'Prowlarr',
         priority: 25,
         seedingTimeMinutes: 0,
+        ratioLimit: 1.5,
         rssEnabled: false,
         audiobookCategories: expect.arrayContaining([3030]),
         ebookCategories: expect.arrayContaining([7020]),