- Replace avatar image from API with gradient avatar from twake-mui (#457)

- Display 2-letter initials (e.g., "JD" for "John Doe") instead of single letter
- Add getInitials helper function in avatarUtils for reusability
- Update Avatar in PeopleSearch, CalendarSearch, and Menubar components
- Remove avatarUrl prop usage across all Avatar components

__test__/utils/avatarUtils.test.ts

@@ -0,0 +1,113 @@
+import { getInitials, stringToGradient } from "../../src/utils/avatarUtils";
+
+jest.mock("@linagora/twake-mui", () => ({
+  nameToColor: jest.fn((name: string) => {
+    if (!name) return undefined;
+    const colors = [
+      "sunrise",
+      "downy",
+      "sugarCoral",
+      "pinkBonnet",
+      "blueMana",
+      "nightBlue",
+      "snowPea",
+      "pluviophile",
+      "cornflower",
+      "paleGreen",
+      "moonBlue",
+    ];
+    const hash = Array.from(name.toUpperCase())
+      .map((letter) => letter.charCodeAt(0))
+      .reduce((sum, number) => sum + number, 0);
+    return colors[hash % colors.length];
+  }),
+}));
+
+describe("avatarUtils", () => {
+  describe("getInitials", () => {
+    it("returns 2-letter initials for full name", () => {
+      expect(getInitials("John Doe")).toBe("JD");
+      expect(getInitials("Alice Smith")).toBe("AS");
+      expect(getInitials("Nguyễn Văn")).toBe("NV");
+    });
+
+    it("returns single letter for single word", () => {
+      expect(getInitials("Alice")).toBe("A");
+      expect(getInitials("John")).toBe("J");
+    });
+
+    it("returns uppercase initials", () => {
+      expect(getInitials("john doe")).toBe("JD");
+      expect(getInitials("ALICE SMITH")).toBe("AS");
+      expect(getInitials("a")).toBe("A");
+    });
+
+    it("handles multiple spaces between words", () => {
+      expect(getInitials("John   Doe")).toBe("JD");
+      expect(getInitials("Alice    Smith   Brown")).toBe("AS");
+    });
+
+    it("handles email addresses", () => {
+      expect(getInitials("john.doe@email.com")).toBe("J");
+      expect(getInitials("test@example.com")).toBe("T");
+    });
+
+    it("handles empty string", () => {
+      expect(getInitials("")).toBe("");
+    });
+
+    it("handles whitespace-only string", () => {
+      expect(getInitials("   ")).toBe("");
+    });
+
+    it("handles single character", () => {
+      expect(getInitials("A")).toBe("A");
+      expect(getInitials("a")).toBe("A");
+    });
+
+    it("handles names with special characters", () => {
+      expect(getInitials("Jean-Pierre")).toBe("J");
+      expect(getInitials("Mary Jane Watson")).toBe("MJ");
+    });
+
+    it("handles unicode characters", () => {
+      expect(getInitials("Nguyễn Văn")).toBe("NV");
+      expect(getInitials("José María")).toBe("JM");
+    });
+
+    it("takes first two words for names with more than two words", () => {
+      expect(getInitials("John Michael Smith")).toBe("JM");
+      expect(getInitials("Alice Bob Charlie")).toBe("AB");
+    });
+  });
+
+  describe("stringToGradient", () => {
+    it("returns color for valid string", () => {
+      const result = stringToGradient("John Doe");
+      expect(result).toBeDefined();
+      expect(typeof result).toBe("string");
+    });
+
+    it("returns same color for same input", () => {
+      const result1 = stringToGradient("John Doe");
+      const result2 = stringToGradient("John Doe");
+      expect(result1).toBe(result2);
+    });
+
+    it("returns undefined for empty string", () => {
+      expect(stringToGradient("")).toBeUndefined();
+    });
+
+    it("returns color for single character", () => {
+      const result = stringToGradient("A");
+      expect(result).toBeDefined();
+      expect(typeof result).toBe("string");
+    });
+
+    it("returns color for email address", () => {
+      const result = stringToGradient("test@example.com");
+      expect(result).toBeDefined();
+      expect(typeof result).toBe("string");
+    });
+  });
+});