Phase 3 : hardening qualite de code - typage strict, securite, dead code, a11y

Config strictement stricte partout (ruff, mypy --strict, bandit, vulture,
import-linter, eslint, stylelint), aucune regle desactivee "pour ne pas
casser le build" - l'existant a ete corrige pour la satisfaire plutot que
l'inverse. Hooks pre-commit locaux (language: system) bloquants.

- Typage mypy --strict propage a tout le moteur (db, screens, auth, core,
  ai, routes, puis publish/scripts/tests/app.py/build_css.py).
- Securite : fuite de handle fichier Windows corrigee dans l'export SCORM
  (routes/publish/export_scorm.py), CSRF/RNG non-crypto/xAPI documentes
  (# nosec, # NOSONAR justifies), nouveau db.json_for_script() (echappe
  "</script>" dans le JSON embarque en <script>, 25 sites).
- Architecture : imports circulaires/F811 nettoyes, contrats
  import-linter respectes, code mort retire (vulture).
- Accessibilite : 69 champs de formulaire sans label correctement
  associe corriges (for/id ou aria-label) sur 11 templates.
- ESLint/Stylelint : lot mecanique JS/CSS, regles ajustees puis
  appliquees (aucune desactivee sans verification individuelle).
- Tests : isolation du compte admin partage (nettoyage ponctuel +
  fixture de teardown automatique en filet de securite), suite complete
  verte (591 tests Python, 241 tests JS).
- SonarQube Community Build self-heberge (Docker + PostgreSQL) : rapport
  complet analyse point par point, faux positifs documentes.
- .gitattributes ajoute (LF force) : core.autocrlf=true sur cette machine
  faisait echouer ESLint (linebreak-style) via un bug connu de git
  (checkout "en place" qui ignore l'eol force sur un fichier deja
  present sur disque - contourne en supprimant puis recreant chaque
  fichier suivi).

djLint (H021, styles inline) volontairement saute pour ce commit -
backlog assume, deja documente, traite dans un lot separe.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

static/js/play/offline/compute-operation.js

@@ -19,50 +19,52 @@ function forgePyMod(a, b) {
 }
 
 function forgeComputeNewValue(operation, current, rawValue, isDecimal) {
-  var round = function (v) { return isDecimal ? v : forgePyInt(v); };
-  if (operation === "definir_texte") return rawValue || "";
-  if (operation === "definir_nombre") {
-    var n = parseFloat(rawValue);
-    return isNaN(n) ? 0 : round(n);
+  const round = function (v) { return isDecimal ? v : forgePyInt(v); };
+  if (operation === 'definir_texte') return rawValue || '';
+  if (operation === 'definir_nombre') {
+    const n = parseFloat(rawValue);
+    return Number.isNaN(n) ? 0 : round(n);
   }
-  if (operation === "definir_bool_vrai") return 1;
-  if (operation === "definir_bool_faux") return 0;
-  if (operation === "basculer_bool") return current ? 0 : 1;
-  if (operation === "incrementer" || operation === "decrementer") {
-    var amount = (rawValue === null || rawValue === undefined || rawValue === "") ? 0 : parseFloat(rawValue);
-    if (isNaN(amount)) amount = 0;
-    if (operation === "decrementer") amount = -amount;
+  if (operation === 'definir_bool_vrai') return 1;
+  if (operation === 'definir_bool_faux') return 0;
+  if (operation === 'basculer_bool') return current ? 0 : 1;
+  if (operation === 'incrementer' || operation === 'decrementer') {
+    let amount = (rawValue === null || rawValue === undefined || rawValue === '') ? 0 : parseFloat(rawValue);
+    if (Number.isNaN(amount)) amount = 0;
+    if (operation === 'decrementer') amount = -amount;
     return round((current || 0) + amount);
   }
-  if (operation === "multiplier") {
-    var factor = (rawValue === null || rawValue === undefined || rawValue === "") ? 1 : parseFloat(rawValue);
-    if (isNaN(factor)) factor = 1;
+  if (operation === 'multiplier') {
+    let factor = (rawValue === null || rawValue === undefined || rawValue === '') ? 1 : parseFloat(rawValue);
+    if (Number.isNaN(factor)) factor = 1;
     return round((current || 0) * factor);
   }
-  if (operation === "diviser" || operation === "modulo") {
-    var divisor = (rawValue === null || rawValue === undefined || rawValue === "") ? 0 : parseFloat(rawValue);
-    if (isNaN(divisor)) divisor = 0;
+  if (operation === 'diviser' || operation === 'modulo') {
+    let divisor = (rawValue === null || rawValue === undefined || rawValue === '') ? 0 : parseFloat(rawValue);
+    if (Number.isNaN(divisor)) divisor = 0;
     if (divisor === 0) return current;
-    var result = operation === "diviser" ? (current || 0) / divisor : forgePyMod(current || 0, divisor);
+    const result = operation === 'diviser' ? (current || 0) / divisor : forgePyMod(current || 0, divisor);
     return round(result);
   }
-  if (operation === "minimum" || operation === "maximum") {
-    var bound = parseFloat(rawValue);
-    if (isNaN(bound)) return current;
-    var res = operation === "minimum" ? Math.max(current || 0, bound) : Math.min(current || 0, bound);
+  if (operation === 'minimum' || operation === 'maximum') {
+    const bound = parseFloat(rawValue);
+    if (Number.isNaN(bound)) return current;
+    const res = operation === 'minimum' ? Math.max(current || 0, bound) : Math.min(current || 0, bound);
     return round(res);
   }
-  if (operation === "alea") {
-    var parts = String(rawValue || "").split(",");
-    var lo = parseFloat(parts[0]), hi = parseFloat(parts[1]);
-    if (isNaN(lo)) lo = 0;
-    if (isNaN(hi)) hi = 0;
-    if (lo > hi) { var tmp = lo; lo = hi; hi = tmp; }
-    if (isDecimal) return Math.random() * (hi - lo) + lo;
-    var iLo = Math.trunc(lo), iHi = Math.trunc(hi);
-    return Math.floor(Math.random() * (iHi - iLo + 1)) + iLo;
+  if (operation === 'alea') {
+    const parts = String(rawValue || '').split(',');
+    let lo = parseFloat(parts[0]); let
+      hi = parseFloat(parts[1]);
+    if (Number.isNaN(lo)) lo = 0;
+    if (Number.isNaN(hi)) hi = 0;
+    if (lo > hi) { const tmp = lo; lo = hi; hi = tmp; }
+    if (isDecimal) return Math.random() * (hi - lo) + lo; // NOSONAR S2245 - tirage de jeu, jamais crypto
+    const iLo = Math.trunc(lo); const
+      iHi = Math.trunc(hi);
+    return Math.floor(Math.random() * (iHi - iLo + 1)) + iLo; // NOSONAR S2245 - tirage de jeu, jamais crypto
   }
-  throw new Error("opération inconnue : " + operation);
+  throw new Error(`opération inconnue : ${operation}`);
 }
 
 // static/js/play/__tests__/ (node:test) — même patron que conditions.js.