feat: add pptx, font, psd, epub converters and context-aware previews

- Wire presentationConverter (pptx read/write via pptxgenjs+jszip)
- Add fontConverter (ttf/otf/woff/woff2 via opentype.js + woff2-encoder)
- Add PSD support via ag-psd in imageConverter
- Add spreadsheetConverter (xlsx/xls/ods via SheetJS)
- Add ebookConverter (epub via jszip)
- Expand data converter with ini/env/properties/ndjson/jsonl/sql formats
- Add context-aware previews for pptx, epub, fonts, and psd in PreviewModal
- Remove unsupported .doc extension from fileDetector
- Replace Node-only wawoff2 with browser-compatible woff2-encoder

package.json

@@ -11,9 +11,11 @@
   "dependencies": {
     "@ffmpeg/ffmpeg": "^0.12.15",
     "@ffmpeg/util": "^0.12.2",
+    "ag-psd": "^30.1.0",
     "docx": "^9.6.0",
     "fast-xml-parser": "^5.4.2",
     "framer-motion": "^12.35.2",
+    "heic2any": "^0.0.4",
     "html2canvas-pro": "^2.0.2",
     "js-yaml": "^4.1.1",
     "jspdf": "^4.2.0",
@@ -21,16 +23,21 @@
     "mammoth": "^1.11.0",
     "marked": "^17.0.4",
     "next": "16.1.6",
+    "opentype.js": "^1.3.4",
     "papaparse": "^5.5.3",
     "pdfjs-dist": "^5.5.207",
+    "pptxgenjs": "^4.0.1",
     "react": "19.2.3",
     "react-dom": "19.2.3",
-    "smol-toml": "^1.6.0"
+    "smol-toml": "^1.6.0",
+    "woff2-encoder": "^2.0.0",
+    "xlsx": "^0.18.5"
   },
   "devDependencies": {
     "@tailwindcss/postcss": "^4",
     "@types/js-yaml": "^4.0.9",
     "@types/node": "^20",
+    "@types/opentype.js": "^1.3.9",
     "@types/papaparse": "^5.5.2",
     "@types/react": "^19",
     "@types/react-dom": "^19",