fix: side peek des bases repasse en vanilla JS + largeur 1100px standard (v7.49.0)

- Panneau peek: les bindings Alpine (x-data absent du conteneur) rendaient
  loovverture et le redimensionnement inoperants -> cblage direct sur le document.
- Helper unique window.fdWirePeekResize (app.js): pointer capture, 300px-90vw,
  clic=fermer, largeur persiste fd_peek_width partagee entre les 4 peeks.
- database-table-container margin:0 (tableau colle a gauche, marge Library).
- .lib-container remonte dans app.css (trash etait pleine largeur), .db-index 1100px.
- ObsiGate verifie sans code: creation .xlsx OK (openpyxl, #186).

app/templates/_database_table.html

@@ -125,13 +125,21 @@
         <div class="db-col-menu-item" id="db-col-insert-right"><span>→┤ Insert right</span></div>
     </div>
 
-    <!-- Side Peek Panel for Database Pages -->
-    <div id="db-side-peek" class="db-side-peek" style="display:none">
-        <div class="db-side-peek-resize" id="db-side-peek-resize"></div>
-        <div class="db-side-peek-header">
-            <button id="db-side-peek-close" class="db-side-peek-close">×</button>
-            <button id="db-side-peek-full" class="db-side-peek-full" title="Open full page">↗</button>
-        </div>
-        <iframe id="db-side-peek-iframe" src="" style="width:100%;height:100%;border:none"></iframe>
+    <!-- Side Peek Panel for Database Pages (vanilla JS, piloté par database_table.js) -->
+    <div id="db-side-peek" class="db-side-peek">
+      <div class="peek-resize-handle" title="Glisser pour redimensionner — cliquer pour fermer"></div>
+      <div class="db-side-peek-header">
+        <button id="db-side-peek-close" title="Close">
+          <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><line x1="18" y1="6" x2="6" y2="18"/><line x1="6" y1="6" x2="18" y2="18"/></svg>
+        </button>
+        <div class="db-side-peek-title" id="db-side-peek-title"></div>
+        <button id="db-side-peek-full" title="Open full page">
+          <svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M18 13v6a2 2 0 01-2 2H5a2 2 0 01-2-2V8a2 2 0 012-2h6"/><polyline points="15 3 21 3 21 9"/><line x1="10" y1="14" x2="21" y2="3"/></svg>
+        </button>
+      </div>
+      <div class="db-side-peek-body">
+        <div class="db-side-peek-loading" id="db-side-peek-loading">Chargement…</div>
+        <iframe id="db-side-peek-iframe" src="about:blank" title="Document" style="width:100%;height:100%;border:none;flex:1;min-height:0;"></iframe>
+      </div>
     </div>
 </div>