fix(input-rich-text) : couleurs de texte et surlignage façon Jira

Ajoute deux boutons à la toolbar avec popover en palette pour
appliquer une couleur de texte ou un surlignage sur la sélection.

- Extensions TipTap : @tiptap/extension-text-style,
  @tiptap/extension-color, @tiptap/extension-highlight (multicolor).
- Palette de 8 couleurs (texte) + 8 pastels (surlignage) + reset.
- Indicateur de couleur active sous l'icône.
- Fermeture du popover sur clic extérieur, Echap, ou clic dans
  l'éditeur.
- Inclut les améliorations rendu/markdown du commit précédent
  (default outputFormat html, normalizeEditorInput, styles deep
  pour h2/h3/p/ul/ol/blockquote).
- Tests : 4 nouveaux cas (15 au total).
- Story et COMPONENTS.md à jour.

Note : les couleurs ne sont pas sérialisables en markdown ; pour
les conserver au save/reload utiliser output-format=\"html\".

Co-Authored-By: RuFlo <ruv@ruv.net>

package-lock.json

@@ -10,7 +10,10 @@
       "dependencies": {
         "@nuxt/icon": "^2.2.1",
         "@nuxtjs/tailwindcss": "^6.14.0",
+        "@tiptap/extension-color": "^3.22.5",
+        "@tiptap/extension-highlight": "^3.22.5",
         "@tiptap/extension-placeholder": "^3.22.5",
+        "@tiptap/extension-text-style": "^3.22.5",
         "@tiptap/pm": "^3.22.5",
         "@tiptap/starter-kit": "^3.22.5",
         "@tiptap/vue-3": "^3.22.5",
@@ -5142,6 +5145,19 @@
         "@tiptap/pm": "3.22.5"
       }
     },
+    "node_modules/@tiptap/extension-color": {
+      "version": "3.22.5",
+      "resolved": "https://registry.npmjs.org/@tiptap/extension-color/-/extension-color-3.22.5.tgz",
+      "integrity": "sha512-4aTygOUlTFBYCvJy67SeKVdXCQw7du3Rj+N5ZutVnDnrpfzUBWsO7f+I+iDS8eMQFbWxVFLlWxGMcTbjtk1a+Q==",
+      "license": "MIT",
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/ueberdosis"
+      },
+      "peerDependencies": {
+        "@tiptap/extension-text-style": "3.22.5"
+      }
+    },
     "node_modules/@tiptap/extension-document": {
       "version": "3.22.5",
       "resolved": "https://registry.npmjs.org/@tiptap/extension-document/-/extension-document-3.22.5.tgz",
@@ -5223,6 +5239,19 @@
         "@tiptap/core": "3.22.5"
       }
     },
+    "node_modules/@tiptap/extension-highlight": {
+      "version": "3.22.5",
+      "resolved": "https://registry.npmjs.org/@tiptap/extension-highlight/-/extension-highlight-3.22.5.tgz",
+      "integrity": "sha512-byWruAOKcqRN0OuzVSKqLLrced3M9AZaR2pD1BV3aUZHzMzeBjLBfByh8s4lExH2Z547xQUdHHnUflBQ572I5A==",
+      "license": "MIT",
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/ueberdosis"
+      },
+      "peerDependencies": {
+        "@tiptap/core": "3.22.5"
+      }
+    },
     "node_modules/@tiptap/extension-horizontal-rule": {
       "version": "3.22.5",
       "resolved": "https://registry.npmjs.org/@tiptap/extension-horizontal-rule/-/extension-horizontal-rule-3.22.5.tgz",
@@ -5373,6 +5402,20 @@
         "@tiptap/core": "3.22.5"
       }
     },
+    "node_modules/@tiptap/extension-text-style": {
+      "version": "3.22.5",
+      "resolved": "https://registry.npmjs.org/@tiptap/extension-text-style/-/extension-text-style-3.22.5.tgz",
+      "integrity": "sha512-jt63jy8YbhZJUGMxTUzeivLhowGtFp6YbCFrrmZJ7G6IHu8X8LJzO81ksz5nT5l8DKpldGwnINUfA6iE91JIAg==",
+      "license": "MIT",
+      "peer": true,
+      "funding": {
+        "type": "github",
+        "url": "https://github.com/sponsors/ueberdosis"
+      },
+      "peerDependencies": {
+        "@tiptap/core": "3.22.5"
+      }
+    },
     "node_modules/@tiptap/extension-underline": {
       "version": "3.22.5",
       "resolved": "https://registry.npmjs.org/@tiptap/extension-underline/-/extension-underline-3.22.5.tgz",