fix(downloads): harden add modal and retry state

Route explicit no-limit speed overrides without inheriting the global cap.

Preserve dotted media titles when switching formats and drain retry gid completions through remember_gid.

src/utils/addDownloadMetadata.test.ts

@@ -2,6 +2,7 @@ import { describe, expect, it } from 'vitest';
 import {
   canSubmitMetadataRows,
   mediaFormatSelectorForRow,
+  mediaFileNameForSelectedFormat,
   metadataSummaryMessage,
   reconcileDownloadRows,
   refreshFailedMetadataRows,
@@ -154,6 +155,36 @@ describe('add download metadata workflow', () => {
     expect(mediaFormatSelectorForRow(failedMedia)).toBeUndefined();
   });
 
+  it('replaces only known media container suffixes when selecting formats', () => {
+    const mediaRow = row({
+      isMedia: true,
+      formats: [
+        {
+          name: '1080p MP4',
+          selector: 'mp4',
+          ext: 'mp4',
+          formatLabel: '1080p',
+          detail: '10 MB',
+          type: 'Video',
+          bytes: 10
+        },
+        {
+          name: '1080p MKV',
+          selector: 'mkv',
+          ext: 'mkv',
+          formatLabel: '1080p',
+          detail: '11 MB',
+          type: 'Video',
+          bytes: 11
+        }
+      ],
+      selectedFormat: 1
+    });
+
+    expect(mediaFileNameForSelectedFormat('Version 1.5', mediaRow)).toBe('Version 1.5.mkv');
+    expect(mediaFileNameForSelectedFormat('Version 1.5.mp4', mediaRow)).toBe('Version 1.5.mkv');
+  });
+
   it('reports fallback and invalid states accurately', () => {
     expect(metadataSummaryMessage([
       row(),

src/utils/addDownloadMetadata.ts

@@ -148,6 +148,38 @@ export const mediaFormatSelectorForRow = (
   return row.formats?.[row.selectedFormat]?.selector;
 };
 
+export const mediaFileNameForSelectedFormat = (
+  fileName: string,
+  row: Pick<AddDownloadDraftRow, 'formats' | 'selectedFormat'>
+): string => {
+  const selectedFormat = row.selectedFormat === undefined
+    ? undefined
+    : row.formats?.[row.selectedFormat];
+  if (!selectedFormat) return canonicalizeDownloadFileName(fileName);
+
+  const cleanFileName = canonicalizeDownloadFileName(fileName);
+  const selectedExt = selectedFormat.ext.replace(/^\.+/, '');
+  if (!selectedExt) return cleanFileName;
+
+  const lowerFileName = cleanFileName.toLowerCase();
+  if (lowerFileName.endsWith(`.${selectedExt.toLowerCase()}`)) {
+    return cleanFileName;
+  }
+
+  const lastDot = cleanFileName.lastIndexOf('.');
+  const currentExt = lastDot > 0 ? cleanFileName.slice(lastDot + 1).toLowerCase() : '';
+  const knownFormatExts = new Set(
+    (row.formats || [])
+      .map(format => format.ext.replace(/^\.+/, '').toLowerCase())
+      .filter(Boolean)
+  );
+  const baseName = currentExt && knownFormatExts.has(currentExt)
+    ? cleanFileName.slice(0, lastDot)
+    : cleanFileName;
+
+  return canonicalizeDownloadFileName(`${baseName}.${selectedExt}`);
+};
+
 export const metadataSummaryMessage = (rows: AddDownloadDraftRow[]): string => {
   if (rows.length === 0) return 'Paste one or more links.';