feat(seo): sitemap + robots.txt + meta OG/Twitter/canonical + site URL

- Installe @astrojs/sitemap ; integre dans astro.config.mjs avec filtre /api/
- Ajoute site: 'https://trans-former.fr' pour canonical absolues
- BaseLayout : props ogImage + canonical + isArticle + articleDate ; meta description/canonical/robots/OG/Twitter Card complets ; suppression doublons
- manifeste.astro : passe isArticle=true pour Schema.org Article
- public/robots.txt : open index + GPTBot/ClaudeBot/Google-Extended/Applebot-Extended/PerplexityBot explicites

package-lock.json

@@ -9,6 +9,7 @@
       "version": "0.0.1",
       "dependencies": {
         "@astrojs/node": "^10.1.0",
+        "@astrojs/sitemap": "^3.7.2",
         "@astrojs/vue": "^6.0.1",
         "@fontsource-variable/roboto-condensed": "^5.2.8",
         "@tailwindcss/vite": "^4.2.4",
@@ -98,6 +99,17 @@
         "node": ">=22.12.0"
       }
     },
+    "node_modules/@astrojs/sitemap": {
+      "version": "3.7.2",
+      "resolved": "https://registry.npmjs.org/@astrojs/sitemap/-/sitemap-3.7.2.tgz",
+      "integrity": "sha512-PqkzkcZTb5ICiyIR8VoKbIAP/laNRXi5tw616N1Ckk+40oNB8Can1AzVV56lrbC5GKSZFCyJYUVYqVivMisvpA==",
+      "license": "MIT",
+      "dependencies": {
+        "sitemap": "^9.0.0",
+        "stream-replace-string": "^2.0.0",
+        "zod": "^4.3.6"
+      }
+    },
     "node_modules/@astrojs/telemetry": {
       "version": "3.3.2",
       "resolved": "https://registry.npmjs.org/@astrojs/telemetry/-/telemetry-3.3.2.tgz",
@@ -2661,6 +2673,24 @@
         "@types/unist": "*"
       }
     },
+    "node_modules/@types/node": {
+      "version": "24.12.4",
+      "resolved": "https://registry.npmjs.org/@types/node/-/node-24.12.4.tgz",
+      "integrity": "sha512-GUUEShf+PBCGW2KaXwcIt3Yk+e3pkKwWKb9GSyM9WQVE+ep2jzmHdGsHzu4wgcZy5fN9FBdVzjpBQsYlpfpgLA==",
+      "license": "MIT",
+      "dependencies": {
+        "undici-types": "~7.16.0"
+      }
+    },
+    "node_modules/@types/sax": {
+      "version": "1.2.7",
+      "resolved": "https://registry.npmjs.org/@types/sax/-/sax-1.2.7.tgz",
+      "integrity": "sha512-rO73L89PJxeYM3s3pPPjiPgVVcymqU490g0YO5n5By0k2Erzj6tay/4lr1CHAAU4JyOWd1rpQ8bCf6cZfHU96A==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*"
+      }
+    },
     "node_modules/@types/unist": {
       "version": "3.0.3",
       "resolved": "https://registry.npmjs.org/@types/unist/-/unist-3.0.3.tgz",
@@ -2936,6 +2966,12 @@
         "url": "https://github.com/sponsors/jonschlinkert"
       }
     },
+    "node_modules/arg": {
+      "version": "5.0.2",
+      "resolved": "https://registry.npmjs.org/arg/-/arg-5.0.2.tgz",
+      "integrity": "sha512-PYjyFOLKQ9y57JvQ6QLo8dAgNqswh8M1RMJYdQduT6xbWSgK36P/Z/v+p888pM69jMMfS8Xd8F6I1kQ/I9HUGg==",
+      "license": "MIT"
+    },
     "node_modules/argparse": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/argparse/-/argparse-2.0.1.tgz",
@@ -6982,6 +7018,25 @@
       "integrity": "sha512-bLGGlR1QxBcynn2d5YmDX4MGjlZvy2MRBDRNHLJ8VI6l6+9FUiyTFNJ0IveOSP0bcXgVDPRcfGqA0pjaqUpfVg==",
       "license": "MIT"
     },
+    "node_modules/sitemap": {
+      "version": "9.0.1",
+      "resolved": "https://registry.npmjs.org/sitemap/-/sitemap-9.0.1.tgz",
+      "integrity": "sha512-S6hzjGJSG3d6if0YoF5kTyeRJvia6FSTBroE5fQ0bu1QNxyJqhhinfUsXi9fH3MgtXODWvwo2BDyQSnhPQ88uQ==",
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "^24.9.2",
+        "@types/sax": "^1.2.1",
+        "arg": "^5.0.0",
+        "sax": "^1.4.1"
+      },
+      "bin": {
+        "sitemap": "dist/esm/cli.js"
+      },
+      "engines": {
+        "node": ">=20.19.5",
+        "npm": ">=10.8.2"
+      }
+    },
     "node_modules/slash": {
       "version": "5.1.0",
       "resolved": "https://registry.npmjs.org/slash/-/slash-5.1.0.tgz",
@@ -7040,6 +7095,12 @@
         "node": ">= 0.8"
       }
     },
+    "node_modules/stream-replace-string": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/stream-replace-string/-/stream-replace-string-2.0.0.tgz",
+      "integrity": "sha512-TlnjJ1C0QrmxRNrON00JvaFFlNh5TTG00APw23j74ET7gkQpTASi6/L2fuiav8pzK715HXtUeClpBTw2NPSn6w==",
+      "license": "MIT"
+    },
     "node_modules/stringify-entities": {
       "version": "4.0.4",
       "resolved": "https://registry.npmjs.org/stringify-entities/-/stringify-entities-4.0.4.tgz",
@@ -7222,6 +7283,12 @@
       "integrity": "sha512-Ql87qFHB3s/De2ClA9e0gsnS6zXG27SkTiSJwjCc9MebbfapQfuPzumMIUMi38ezPZVNFcHI9sUIepeQfw8J8Q==",
       "license": "MIT"
     },
+    "node_modules/undici-types": {
+      "version": "7.16.0",
+      "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-7.16.0.tgz",
+      "integrity": "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw==",
+      "license": "MIT"
+    },
     "node_modules/unicorn-magic": {
       "version": "0.4.0",
       "resolved": "https://registry.npmjs.org/unicorn-magic/-/unicorn-magic-0.4.0.tgz",