fix: Sem. préc. HEAD→GET, prevMeetings cache, remove footer

- investinglive: tryUrl HEAD→GET + res.body?.cancel() (WordPress bloque HEAD)
  fenêtre recherche article préc. élargie 21→28 jours
- rateprobability: CBRatePath + prevMeetings/prevWeekDate, loadPrevWeekCachedBody()
  fetchAllCBPaths enrichit prevMeetings depuis snapshot GitHub Actions
- fetch-rate-data.mjs: rotation current→previousWeek (5–9 jours) pour Rate Curve
- CurrencyCard: rateCurveData préfère prevMeetings (exact/meeting) > ilDelta (approx)
  légende hasPrevCurve pilote affichage ligne bleue et label date
- page.tsx: suppression footer Sources/LLM, remplacement par pb-12

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

.github/scripts/fetch-rate-data.mjs

@@ -1,6 +1,6 @@
 // Runs in GitHub Actions (not Vercel) — fetches from rateprobability.com
 // GitHub Actions IPs are not blocked by the site.
-import { writeFileSync, mkdirSync } from "fs";
+import { writeFileSync, mkdirSync, readFileSync } from "fs";
 
 const CB_KEYS = [
   ["USD", "fed"],
@@ -45,10 +45,37 @@ for (const [ccy, slug] of CB_KEYS) {
   await new Promise(r => setTimeout(r, 300)); // 300ms entre requêtes
 }
 
+// Rotation : si les données existantes datent de 5–9 jours → les sauvegarder comme previousWeek
+let previousWeek = null;
+let previousWeekFetchedAt = null;
+try {
+  const existing = JSON.parse(readFileSync("data/rate-probabilities.json", "utf8"));
+  const ageMs = Date.now() - new Date(existing.fetchedAt).getTime();
+  const day = 86400000;
+  if (ageMs >= 5 * day && ageMs <= 9 * day) {
+    // Les données courantes datent d'une semaine → les promouvoir en previousWeek
+    previousWeek = existing.data;
+    previousWeekFetchedAt = existing.fetchedAt;
+    console.log(`\nRotated existing data (${(ageMs / day).toFixed(1)}d old) to previousWeek`);
+  } else if (existing.previousWeek && existing.previousWeekFetchedAt) {
+    // Conserver le previousWeek existant s'il est encore dans la fenêtre utile (< 11 jours)
+    const prevAge = Date.now() - new Date(existing.previousWeekFetchedAt).getTime();
+    if (prevAge < 11 * day) {
+      previousWeek = existing.previousWeek;
+      previousWeekFetchedAt = existing.previousWeekFetchedAt;
+    }
+  }
+} catch { /* pas de fichier existant */ }
+
 mkdirSync("data", { recursive: true });
 writeFileSync(
   "data/rate-probabilities.json",
-  JSON.stringify({ data: results, fetchedAt: new Date().toISOString() }, null, 2)
+  JSON.stringify({
+    data: results,
+    fetchedAt: new Date().toISOString(),
+    ...(previousWeek ? { previousWeek, previousWeekFetchedAt } : {}),
+  }, null, 2)
 );
 
 console.log(`\nSaved ${Object.keys(results).length} CBs: ${Object.keys(results).join(", ")}`);
+if (previousWeek) console.log(`previousWeek preserved (${Object.keys(previousWeek).join(", ")})`);