Add My Docs picker to deep-research, advocate, barnevernet, korrespond, citations

- PHP: Add docPickerSection (button + chips + hidden input) to all 5 tool pages
- JS: Send doc_ids in payload for deep-research, advocate, barnevernet, korrespond
- Backend: Inject selected corpus doc content into paste_text/narrative/notes via dbnToolsInjectDocContent
- Citations: Add upload zone (file → api/extract.php → textarea) + paste textarea with live Norwegian legal reference extraction (regex) + ref chips → title search; doc picker populates titleInput via MutationObserver

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

assets/js/korrespond.js

@@ -260,7 +260,8 @@
   function buildPayload(forceDraft) {
     const deadlines = [];
     if (els.deadline.value.trim()) deadlines.push(els.deadline.value.trim());
-    return {
+    const korrDocIds = (document.getElementById('docPickerIds')?.value || '').split(',').map(Number).filter(Boolean);
+    const payload = {
       mode:           getRadio(els.modeRadios) || 'initiate',
       recipient_body: els.bodySelect.value || 'other',
       output_type:    getRadio(els.outputRadios) || 'email',
@@ -276,6 +277,8 @@
       force_draft:    !!forceDraft,
       use_my_case:    (typeof window.dbnGetUseMyCase === 'function') ? window.dbnGetUseMyCase() : false,
     };
+    if (korrDocIds.length) payload.doc_ids = korrDocIds;
+    return payload;
   }
 
   async function runRequest(forceDraft) {