feat(domain,application,infrastructure,backend,web-server,app-tauri,frontend): lot utilisateur #325 #326 — icônes projet avec watermark CLI custom et localisation FR/EN (QA verte)

Lot en un seul commit: les deux features partagent les mêmes contrats
(domain/settings.rs, DTO, commandes Tauri/HTTP, web-server) et les mêmes
surfaces UI — la séparation par fichiers était impossible sans chirurgie
de hunks risquant des états intermédiaires non compilables (convention
lot des batches #310-#313 et #315).

#325 — icône configurable par projet, watermark CLI custom:
- domaine: ProjectIconSet (devicon, simple-icons, lucide, idea),
  ProjectIconRef validé (nom ASCII 1..=64, -_. internes), champ icon
  optionnel sur ProjectSettings; sérialisation camelCase et try_from
  strict
- application: UpdateProjectSettings.execute accepte un patch
  theme_color OU icon (absent = inchangé, null = défaut produit), tests
  in-dependants avec store mémoire
- backend/app-tauri/web-server: ProjectIconRefDto, UpdateProjectSettingsRequestDto
  avec icon optionnel (désérialisation additive), commandes
  update_project_settings alignées Tauri/HTTP, tests DTO et HTTP
  (défaut null, set, clear, nom invalide rejeté)
- frontend: catalogue projectIcons (recherche EN), ProjectIconPicker en
  grille multi-lignes dans Paramètres projet, affichage de l'icône dans
  ProjectTabs et watermark grand format à faible opacité en fond de CLI
  custom; ports ProjectSettings.icon, Partial<ProjectSettings>,
  adapters tauri/mock/http et tests alignés

#326 — localisation FR/EN et traduction des textes IdeA:
- domaine: IdeaLanguage (fr | en), champ language optionnel sur
  IdeaUserSettings (absence = défaut produit, série additive validée)
- backend/web-server: UserSettingsDto.language, update_user_settings
  accepte language, tests HTTP alignés; fixtures structured_launch_d3
  mises à jour
- frontend: i18n/ (catalogue FR/EN, I18nProvider, scan anti-régression
  des sources visibles), GeneralSettings avec sélecteur de langue dans
  les paramètres, setupI18n dans vitest; migration de l'ensemble des
  textes hardcodés vers le catalogue sur toutes les surfaces (agents,
  layout, projets, tickets, sprints, web, plugins, permissions, git,
  templates, skills, mémoire, model servers, embedder, first-run,
  devices, scheduled tasks, workstate, dialogs), FR conservé par défaut;
  recherche d'icônes #325 en anglais conformément au ticket

QA verte sur feature/batch-325-326-project-icons-localisation. Aucun push.

frontend/src/adapters/http/index.ts

@@ -166,7 +166,7 @@ class HttpUserSettingsGateway implements UserSettingsGateway {
     return this.http.invoke<UserSettings>("read_user_settings");
   }
 
-  updateUserSettings(settings: UserSettings): Promise<UserSettings> {
+  updateUserSettings(settings: Partial<UserSettings>): Promise<UserSettings> {
     return this.http.invoke<UserSettings>("update_user_settings", { request: settings });
   }
 }

frontend/src/adapters/http/requestResponseGateways.ts

@@ -141,9 +141,9 @@ export class HttpProjectGateway implements ProjectGateway {
   readProjectSettings(projectId: string): Promise<ProjectSettings> {
     return this.http.invoke<ProjectSettings>("read_project_settings", { projectId });
   }
-  updateProjectSettings(projectId: string, settings: ProjectSettings): Promise<ProjectSettings> {
+  updateProjectSettings(projectId: string, settings: Partial<ProjectSettings>): Promise<ProjectSettings> {
     return this.http.invoke<ProjectSettings>("update_project_settings", {
-      request: { projectId, themeColor: settings.themeColor },
+      request: { projectId, ...settings },
     });
   }
   listProjectFiles(projectId: string, path: string): Promise<ProjectFileListing> {

frontend/src/adapters/mock/index.ts

@@ -1466,20 +1466,26 @@ export class MockProjectGateway implements ProjectGateway {
     if (!this.projects.some((project) => project.id === projectId)) {
       throw { code: "NOT_FOUND", message: `project ${projectId} not found` };
     }
-    return this.settings.get(projectId) ?? { themeColor: null };
+    return this.settings.get(projectId) ?? { themeColor: null, icon: null };
   }
 
   async updateProjectSettings(
     projectId: string,
-    settings: ProjectSettings,
+    settings: Partial<ProjectSettings>,
   ): Promise<ProjectSettings> {
     if (!this.projects.some((project) => project.id === projectId)) {
       throw { code: "NOT_FOUND", message: `project ${projectId} not found` };
     }
-    if (settings.themeColor !== null && !/^#[0-9A-Fa-f]{6}$/.test(settings.themeColor)) {
+    if (settings.themeColor !== undefined && settings.themeColor !== null && !/^#[0-9A-Fa-f]{6}$/.test(settings.themeColor)) {
       throw { code: "INVALID", message: "themeColor must use #RRGGBB" };
     }
-    const stored = { themeColor: settings.themeColor?.toUpperCase() ?? null };
+    const previous = this.settings.get(projectId) ?? { themeColor: null, icon: null };
+    const stored = {
+      themeColor: settings.themeColor === undefined
+        ? previous.themeColor
+        : settings.themeColor?.toUpperCase() ?? null,
+      icon: settings.icon === undefined ? (previous.icon ?? null) : settings.icon,
+    };
     this.settings.set(projectId, stored);
     return stored;
   }
@@ -5015,14 +5021,14 @@ export function createMockGateways(): Gateways {
 }
 
 export class MockUserSettingsGateway implements UserSettingsGateway {
-  private settings: UserSettings = { defaultAgentTerminalInterface: null };
+  private settings: UserSettings = { defaultAgentTerminalInterface: null, language: null };
 
   async readUserSettings(): Promise<UserSettings> {
     return { ...this.settings };
   }
 
-  async updateUserSettings(settings: UserSettings): Promise<UserSettings> {
-    this.settings = { ...settings };
+  async updateUserSettings(settings: Partial<UserSettings>): Promise<UserSettings> {
+    this.settings = { ...this.settings, ...settings };
     return { ...this.settings };
   }
 }

frontend/src/adapters/project.test.ts

@@ -63,4 +63,17 @@ describe("TauriProjectGateway invoke payloads", () => {
       request: { projectId: "proj-1" },
     });
   });
+
+  it("passes project icon updates through the additive settings request", async () => {
+    const gateway = new TauriProjectGateway();
+    await gateway.updateProjectSettings("proj-1", {
+      icon: { set: "devicon", name: "typescript" },
+    });
+    expect(invoke).toHaveBeenCalledWith("update_project_settings", {
+      request: {
+        projectId: "proj-1",
+        icon: { set: "devicon", name: "typescript" },
+      },
+    });
+  });
 });

frontend/src/adapters/project.ts

@@ -84,10 +84,10 @@ export class TauriProjectGateway implements ProjectGateway {
 
   updateProjectSettings(
     projectId: string,
-    settings: ProjectSettings,
+    settings: Partial<ProjectSettings>,
   ): Promise<ProjectSettings> {
     return invoke<ProjectSettings>("update_project_settings", {
-      request: { projectId, themeColor: settings.themeColor },
+      request: { projectId, ...settings },
     });
   }
 

frontend/src/adapters/userSettings.test.ts

@@ -0,0 +1,15 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+const invoke = vi.fn();
+vi.mock("@tauri-apps/api/core", () => ({ invoke: (...args: unknown[]) => invoke(...args) }));
+
+import { TauriUserSettingsGateway } from "./userSettings";
+
+describe("TauriUserSettingsGateway", () => {
+  beforeEach(() => invoke.mockReset().mockResolvedValue({ defaultAgentTerminalInterface: null, language: "en" }));
+
+  it("persists language without overwriting unrelated user settings", async () => {
+    await new TauriUserSettingsGateway().updateUserSettings({ language: "en" });
+    expect(invoke).toHaveBeenCalledWith("update_user_settings", { request: { language: "en" } });
+  });
+});

frontend/src/adapters/userSettings.ts

@@ -7,7 +7,7 @@ export class TauriUserSettingsGateway implements UserSettingsGateway {
     return invoke<UserSettings>("read_user_settings");
   }
 
-  updateUserSettings(settings: UserSettings): Promise<UserSettings> {
+  updateUserSettings(settings: Partial<UserSettings>): Promise<UserSettings> {
     return invoke<UserSettings>("update_user_settings", { request: settings });
   }
 }