Fix footer version, improve PDF filter detection

- options.html/js: Footer version now reads dynamically from manifest via
  api.runtime.getManifest().version instead of hardcoded v0.3.0
- document-scanner.js: Increase FlateDecode lookback from 200 to 500 bytes
  (real PDF stream dictionaries are often larger than 200 bytes), and support
  array form /Filter [/FlateDecode] alongside the scalar form

https://claude.ai/code/session_01ReZUeR1nrYzJeX7fTqwXMw

src/lib/document-scanner.js

@@ -257,8 +257,8 @@ const DocumentScanner = {
 
         // Try to decompress if FlateDecode
         let content = streamData;
-        const filterMatch = str.slice(Math.max(0, match.index - 200), match.index)
-          .match(/\/Filter\s*\/FlateDecode/);
+        const dictSlice = str.slice(Math.max(0, match.index - 500), match.index);
+        const filterMatch = dictSlice.match(/\/Filter\s*(?:\/FlateDecode|\[\/FlateDecode\]|\[.*?\/FlateDecode.*?\])/);
 
         if (filterMatch) {
           try {

src/options/options.html

@@ -601,7 +601,7 @@
     </section>
 
     <footer>
-      <p>Silent Send v0.3.0</p>
+      <p id="footerVersion">Silent Send</p>
     </footer>
   </div>
 

src/options/options.js

@@ -28,6 +28,9 @@ document.addEventListener('DOMContentLoaded', async () => {
   $('#maxLogEntries').value = settings.maxLogEntries || 200;
   $('#browserSync').checked = settings.browserSync === true;
 
+  const { version } = api.runtime.getManifest();
+  $('#footerVersion').textContent = `Silent Send v${version}`;
+
   renderMappings();
   renderPasswords();
   renderDomains();