feat: page interactive, démos Play/Step et simulateur Carnot

Ajoute le pipeline PageSpec (validation, rendu, publication /p/{slug}),
les démos TipTap /demo, et le simulateur Carnot (modes frigo/PAC/moteur,
énergie kJ vs puissance W, unités K/°C/°F) avec correctifs d’équations KaTeX.

Co-authored-by: Cursor <cursoragent@cursor.com>

memento-note/locales/en.json

@@ -38,7 +38,24 @@
     "createYourSpaceSubtitle": "Join the new era of smart note-taking.",
     "forgot": "Forgot?",
     "backToSite": "Back to site",
-    "privacyTerms": "© 2025 Memento Labs — Privacy · Terms"
+    "privacyTerms": "© 2025 Memento Labs — Privacy · Terms",
+    "checkEmailTitle": "Check your email",
+    "checkEmailDescription": "We sent a confirmation link to {email}. Open it to activate your account before signing in.",
+    "checkEmailDescriptionGeneric": "We sent a confirmation link to your email. Open it to activate your account before signing in.",
+    "resendVerification": "Resend confirmation email",
+    "verifyResent": "Confirmation email sent. Check your inbox.",
+    "verifyResendFailed": "Could not send the confirmation email. Try again later.",
+    "verifyMissingEmail": "Enter your email address.",
+    "verifyLoading": "Confirming your email…",
+    "verifySuccessTitle": "Email confirmed",
+    "verifySuccessDescription": "Your account is ready. You can now sign in.",
+    "verifyExpiredTitle": "Link expired",
+    "verifyExpiredDescription": "This confirmation link has expired. Request a new one.",
+    "verifyInvalidTitle": "Invalid link",
+    "verifyInvalidDescription": "This confirmation link is invalid or already used.",
+    "emailNotVerified": "Please confirm your email before signing in.",
+    "emailVerifiedBanner": "Email confirmed. You can sign in now.",
+    "invalidCredentials": "Invalid email or password."
   },
   "sidebar": {
     "notes": "Notes",
@@ -792,6 +809,18 @@
     "formal": "Formal",
     "casual": "Casual"
   },
+  "interactiveDemo": {
+    "invalid": "Invalid interactive demo",
+    "empty": "Interactive demo unavailable",
+    "step": "step",
+    "speed": "Playback speed",
+    "needMoreText": "Select at least ~20 words (or write more content) to generate a demo",
+    "generating": "Generating interactive demo…",
+    "generateSuccess": "Interactive demo inserted",
+    "generateFailed": "Demo generation failed",
+    "insertFailed": "Could not insert the demo",
+    "quotaExceeded": "Not enough AI quota"
+  },
   "memoryEcho": {
     "title": "I noticed something...",
     "description": "Proactive connections between your notes",
@@ -1602,7 +1631,58 @@
       "notSynced": "Not synced yet (cron /api/cron/sync-usage)",
       "byFeature": "By feature (PostgreSQL)",
       "topUsers": "Top users",
-      "noUsageData": "No usage data for this period yet"
+      "noUsageData": "No usage data for this period yet",
+      "healthTitle": "Stripe health check",
+      "healthDescription": "Runtime status of keys, webhooks, price IDs and billing flag (secrets are never shown).",
+      "healthSecret": "Secret key (server)",
+      "healthPublishable": "Publishable key",
+      "healthWebhook": "Webhook secret",
+      "healthBillingFlag": "Billing enabled",
+      "healthTrial": "Free trial",
+      "trialDaysValue": "{days} days on first checkout",
+      "modeTest": "Test mode (sk_test_…)",
+      "modeLive": "Live mode (sk_live_…)",
+      "modePlaceholder": "Placeholder / invalid key",
+      "modeMissing": "Not configured",
+      "configured": "Configured",
+      "missing": "Missing",
+      "enabled": "Enabled",
+      "disabled": "Disabled",
+      "priceStatusTitle": "Price IDs vs Stripe",
+      "colKey": "Plan",
+      "colPriceId": "Price ID",
+      "colSource": "Source",
+      "colStripe": "Stripe amount",
+      "priceError": "Lookup failed",
+      "inactive": "inactive",
+      "notChecked": "Not checked (no Stripe key)",
+      "subsTitle": "Subscriptions overview",
+      "subsDescription": "Counts from the local database (synced via Stripe webhooks).",
+      "statPaid": "Active + trial",
+      "statTrialing": "On trial",
+      "statPastDue": "Past due",
+      "statCanceling": "Cancel at period end",
+      "byTier": "By tier",
+      "byStatus": "By status",
+      "usersWithoutSub": "Users with no Subscription row",
+      "noSubs": "No subscriptions yet",
+      "recentSubs": "Recent paid / trial accounts",
+      "colUser": "User",
+      "colTier": "Tier",
+      "colStatus": "Status",
+      "colPeriod": "Period / trial end",
+      "canceling": "canceling",
+      "manualTier": "manual (no Stripe sub)",
+      "trialUntil": "Trial until {date}",
+      "testGuideTitle": "How to test Stripe locally",
+      "testGuideDescription": "Checklist to validate checkout, webhooks and trial.",
+      "testStep1": "Stripe Dashboard → Test mode ON. Create Pro/Business products + monthly/annual prices + credit packs.",
+      "testStep2": "Put sk_test_…, pk_test_… in .env. Put price_… IDs in Admin → Billing (or env) and enable billing.",
+      "testStep3": "Copy the whsec_… into STRIPE_WEBHOOK_SECRET and restart the app.",
+      "testStep4": "npm run dev → open /settings/billing as a BASIC user.",
+      "testStep5": "Start Pro checkout. Card: 4242 4242 4242 4242, any future expiry, any CVC. Expect a 7-day trial.",
+      "testStep6": "Confirm Admin → Billing shows TRIALING, and /settings/billing shows the trial end date.",
+      "testCardHint": "Other cards: 4000000000009995 = payment fails · 4000002500003155 = 3D Secure. Never use real cards in test mode."
     },
     "dashboard": {
       "title": "Dashboard",
@@ -1812,6 +1892,8 @@
     "featureBrainstormCreate": "Brainstorm creations",
     "featureBrainstormSessions": "Brainstorm sessions",
     "featureCharts": "AI Charts",
+    "featureInteractiveDemo": "Interactive demos",
+    "featureInteractivePage": "Interactive pages",
     "featurePublishEnhance": "AI Publishing",
     "featureBrainstormExpand": "Brainstorm expansions",
     "featureBrainstormEnrich": "Brainstorm enrichments",
@@ -2579,6 +2661,8 @@
     "slashTableDesc": "Insert a simple grid",
     "slashDatabase": "Structured View",
     "slashDatabaseDesc": "Embed your notebook's structured data",
+    "slashInteractiveDemo": "Interactive Demo",
+    "slashInteractiveDemoDesc": "AI step-by-step teaching demo (Play / Step)",
     "slashToggle": "Toggle Section",
     "slashToggleDesc": "Create a collapsible section",
     "slashCallout": "Callout",
@@ -2726,6 +2810,21 @@
     "publishTemplateMagazine": "Magazine article",
     "publishTemplateBrief": "Expert brief",
     "publishTemplateEssay": "Essay",
+    "publishTemplateInteractivePage": "Interactive page",
+    "publishInteractivePage": "Interactive page",
+    "publishInteractivePageHint": "AI-generated page: hero, sections, Play/Step demos — 20 credits",
+    "publishInteractivePageGenerating": "Building interactive page…",
+    "publishInteractivePageGeneratingWait": "Almost ready…",
+    "publishInteractivePageGeneratingLong": "Still working…",
+    "publishInteractivePagePlanning": "Analyzing content — planning the page…",
+    "publishInteractivePageSectionProgress": "Section {current}/{total}: {title}",
+    "publishInteractivePageFallback": "AI generation unavailable — showing simplified page",
+    "publishInteractivePagePartialFallback": "Some sections were generated in simplified mode",
+    "publishInteractivePageTooShort": "Note too short — add more content and try again",
+    "publishInteractivePageSuccess": "Interactive page published!",
+    "publishInteractivePageFailed": "Interactive page generation failed",
+    "publishInteractivePagePreviewHint": "Preview — review, then publish to the public URL",
+    "publishInteractivePageConfirm": "Publish page",
     "publishAiSuccess": "AI-enhanced page published!",
     "publishRewriteLabel": "Rewrite for the web",
     "publishRewriteOnHint": "Structures your editor blocks (exercises, toggles, callouts) for the web — AI writes only the intro",
@@ -3381,7 +3480,11 @@
     "fetchStatusFailed": "Failed to fetch billing status",
     "fetchQuotasFailed": "Failed to load credit usage",
     "fetchInvoicesFailed": "Failed to load billing history.",
-    "savePercent": "Save ~17%"
+    "savePercent": "Save ~17%",
+    "startTrialCta": "Start {days}-day free trial",
+    "trialFeature": "{days}-day free trial (card required)",
+    "trialEndsOn": "Your free trial ends on {date}. You will then be billed automatically.",
+    "trialEndsLabel": "Trial ends"
   },
   "quotaPaywall": {
     "title": "Out of AI credits",
@@ -3528,6 +3631,12 @@
       "perMonthAnnual": "/mo, billed yearly",
       "perUser": "+ €3.90/user",
       "perUserAnnual": "+ €2.90/user, yearly",
+      "savePercent": "Save ~17%",
+      "proMonthly": "€9.90",
+      "proAnnualMonthly": "€8.25",
+      "businessMonthly": "€29.90",
+      "businessAnnualMonthly": "€24.92",
+      "enterprisePrice": "Custom",
       "popular": "Most chosen",
       "basic": {
         "name": "Basic",
@@ -3572,7 +3681,10 @@
         "feature4": "Dedicated support",
         "feature5": "Live onboarding"
       },
-      "basicPrice": "Free"
+      "basicPrice": "Free",
+      "trialBadge": "{days}-day free trial",
+      "trialFeature": "{days}-day free trial (card required)",
+      "trialCta": "Start {days}-day free trial"
     },
     "cta": {
       "title": "Stop losing your best ideas.",