feat: improve TagInput component with dropdown positioning

- Added logic to calculate and update the dropdown position dynamically based on the input container's position, enhancing the user experience.
- Implemented portal rendering for the suggestions dropdown to avoid z-index issues, ensuring it displays correctly above other elements.
- Refactored the component to use a `containerRef` for better positioning management.

src/components/ui/TagInput.tsx

@@ -1,6 +1,7 @@
 'use client';
 
 import { useState, useRef, useEffect } from 'react';
+import { createPortal } from 'react-dom';
 import { Tag } from '@/lib/types';
 import { useTagsAutocomplete } from '@/hooks/useTags';
 import { Badge } from './Badge';
@@ -25,11 +26,25 @@ export function TagInput({
   const [inputValue, setInputValue] = useState('');
   const [showSuggestions, setShowSuggestions] = useState(false);
   const [selectedIndex, setSelectedIndex] = useState(-1);
+  const [dropdownPosition, setDropdownPosition] = useState({ top: 0, left: 0, width: 0 });
   const inputRef = useRef<HTMLInputElement>(null);
   const suggestionsRef = useRef<HTMLDivElement>(null);
+  const containerRef = useRef<HTMLDivElement>(null);
 
   const { suggestions, loading, searchTags, clearSuggestions, loadPopularTags } = useTagsAutocomplete();
 
+  // Calculer la position du dropdown
+  const updateDropdownPosition = () => {
+    if (containerRef.current) {
+      const rect = containerRef.current.getBoundingClientRect();
+      setDropdownPosition({
+        top: rect.bottom + window.scrollY + 4,
+        left: rect.left + window.scrollX,
+        width: rect.width
+      });
+    }
+  };
+
   // Rechercher des suggestions quand l'input change
   useEffect(() => {
     if (inputValue.trim()) {
@@ -42,6 +57,24 @@ export function TagInput({
     }
   }, [inputValue, searchTags, clearSuggestions]);
 
+  // Mettre à jour la position du dropdown quand nécessaire
+  useEffect(() => {
+    if (showSuggestions) {
+      updateDropdownPosition();
+      
+      const handleResize = () => updateDropdownPosition();
+      const handleScroll = () => updateDropdownPosition();
+      
+      window.addEventListener('resize', handleResize);
+      window.addEventListener('scroll', handleScroll, true);
+      
+      return () => {
+        window.removeEventListener('resize', handleResize);
+        window.removeEventListener('scroll', handleScroll, true);
+      };
+    }
+  }, [showSuggestions]);
+
   const addTag = (tagName: string) => {
     const trimmedTag = tagName.trim();
     if (trimmedTag && !tags.includes(trimmedTag) && tags.length < maxTags) {
@@ -96,6 +129,7 @@ export function TagInput({
   };
 
   const handleFocus = () => {
+    updateDropdownPosition();
     if (inputValue.trim()) {
       // Si il y a du texte, afficher les suggestions existantes
       setShowSuggestions(true);
@@ -108,7 +142,7 @@ export function TagInput({
   };
 
   return (
-    <div className={`relative ${className}`}>
+    <div ref={containerRef} className={`relative ${className}`}>
       {/* Container des tags et input */}
       <div className="min-h-[42px] p-2 border border-[var(--border)] rounded-lg bg-[var(--input)] focus-within:border-[var(--primary)] focus-within:ring-1 focus-within:ring-[var(--primary)]/20 transition-colors">
         <div className="flex flex-wrap gap-1 items-center">
@@ -148,11 +182,16 @@ export function TagInput({
         </div>
       </div>
 
-      {/* Suggestions dropdown */}
-      {showSuggestions && (suggestions.length > 0 || loading) && (
+      {/* Suggestions dropdown rendu via portail pour éviter les problèmes de z-index */}
+      {showSuggestions && (suggestions.length > 0 || loading) && typeof window !== 'undefined' && createPortal(
         <div
           ref={suggestionsRef}
-          className="absolute top-full left-0 right-0 mt-1 bg-[var(--card)] border border-[var(--border)] rounded-lg shadow-lg z-[9999] max-h-64 overflow-y-auto"
+          className="fixed bg-[var(--card)] border border-[var(--border)] rounded-lg shadow-xl z-[9999] max-h-64 overflow-y-auto"
+          style={{
+            top: dropdownPosition.top,
+            left: dropdownPosition.left,
+            width: dropdownPosition.width
+          }}
         >
           {loading ? (
             <div className="p-3 text-center text-[var(--muted-foreground)] text-sm">
@@ -185,7 +224,8 @@ export function TagInput({
               ))}
             </div>
           )}
-        </div>
+        </div>,
+        document.body
       )}
 
       {/* Indicateur de limite */}