docs: note which files the preview shows

docs/parity/03-email-viewer.md

@@ -175,7 +175,7 @@ RN has a solid single-message reader (WebView body with CSP, shrink-to-fit + pin
   - What RN does: single tap follows the global `mailAttachmentAction`; `jszip` is already a dependency (`package.json:36`) but unused for mail.
   - Fix hint: long-press sheet with "Open / Save / Share"; a "Download all" entry building the zip with `jszip` into `Paths.cache` then sharing.
 
-- [x] **In-app attachment preview (images, PDF, text, audio/video) is absent; iOS "Preview" is just the share sheet — fixed in d2ed27f** — `P3` — `partial`
+- [x] **In-app attachment preview (images, PDF, text, audio/video) is absent; iOS "Preview" is just the share sheet — fixed in d2ed27f; audio/video, HTML, Markdown, SVG, Android PDFs and ZIPs since 0.1.80-0.1.82** — `P3` — `partial`
   - What WEB does: `FilePreviewModal` for images/PDF (bytes handed to pdf.js, #871)/text/markdown/audio/video/eml, script-bearing types forced to download (`components/mail/mail-app.tsx:2887-2935`, `lib/file-preview.ts:29-92`).
   - What RN does: Android hands the file to an external viewer via `ACTION_VIEW`, iOS opens the share sheet (`src/lib/email-export.ts:64-79`, `115-141`); nothing is previewed inside the app.
   - Fix hint: for images/PDF/text open a modal `WebView` on the cached `file://` (or use `expo-file-system`'s `File.uri` with a QuickLook bridge on iOS); keep the external-viewer path as fallback.

docs/parity/07-filters-vacation-files.md

@@ -110,7 +110,7 @@ Filters: RN carries a byte-for-byte port of WEB's Sieve parser/generator/tests a
   - What RN does: `getDocumentAsync({ multiple: false })` (`src/screens/FilesScreen.tsx:357-360`); uploading the same name twice creates two nodes with the same name.
   - Fix hint: `multiple: true` + sequential upload loop; reuse WEB's `getUniqueName` against `visibleFiles`.
 
-- [x] **No in-app preview (image/text/markdown/PDF/audio/video/eml)** — `P2` — `missing` — done in 409cdb1 (images, text and source files, `.eml`, and PDFs on iOS open in the reader's preview; PDFs on Android, audio, video, HTML and Markdown still go to another app)
+- [x] **No in-app preview (image/text/markdown/PDF/audio/video/eml)** — `P2` — `missing` — done in 409cdb1 (images, text and source files, `.eml`, and PDFs on iOS open in the reader's preview); since 0.1.80/0.1.81 also audio, video, SVG/ICO, HTML, Markdown, PDFs on Android (native `PdfRenderer`) and ZIP listings, through the one preview the reader, list, Files and compose share (`src/components/email/use-file-preview.ts`)
   - What WEB does: `ImagePreviewModal` and `FilePreviewModal` (text, markdown, PDF incl. mobile pdf.js viewer, audio, video, EML) chosen via `getFilePreviewKind` (`lib/file-preview.ts:29-68`; `components/files/file-preview-modal.tsx`, `image-preview-modal.tsx`, `pdf-mobile-viewer.tsx`; `files-app.tsx:487-495`, `690-708`).
   - What RN does: tapping a file calls `shareAttachment` which downloads to cache and hands off to the OS share/viewer sheet (`src/screens/FilesScreen.tsx:248-258`; `src/lib/email-export.ts` "preview" variant). Works but there is no inline viewer and no "recent files" tracking.
   - Fix hint: reuse whatever attachment viewer the mail area has (image modal / WebView for text+PDF); N/A if the team decides the OS viewer is the mobile answer - then close this item.

src/screens/FilesScreen.tsx

@@ -360,8 +360,8 @@ export default function FilesScreen() {
     }
   }, [t]);
 
-  // Tap on a file: the in-app preview for the types it shows (images, text
-  // and code, .eml, PDFs on iOS), the other app for the rest.
+  // Tap on a file: the in-app preview for the types it shows (lib/file-preview),
+  // the other app for the rest.
   const openFile = useCallback((row: FileRow) => {
     if (canPreviewInApp(row)) setPreviewTarget(row);
     else void openFileWith(row);