Add player character management feature

Persistent player character templates (name, AC, HP, color, icon) with
full CRUD, bestiary-style search to add PCs to encounters with pre-filled
stats, and color/icon visual distinction in combatant rows. Also stops
the stat block panel from auto-opening when adding a creature.

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

packages/domain/src/__tests__/create-player-character.test.ts

@@ -0,0 +1,227 @@
+import { describe, expect, it } from "vitest";
+import { createPlayerCharacter } from "../create-player-character.js";
+import type { PlayerCharacter } from "../player-character-types.js";
+import { playerCharacterId } from "../player-character-types.js";
+import { isDomainError } from "../types.js";
+
+const id = playerCharacterId("pc-1");
+
+function success(
+	characters: readonly PlayerCharacter[],
+	name: string,
+	ac: number,
+	maxHp: number,
+	color = "blue",
+	icon = "sword",
+) {
+	const result = createPlayerCharacter(
+		characters,
+		id,
+		name,
+		ac,
+		maxHp,
+		color,
+		icon,
+	);
+	if (isDomainError(result)) {
+		throw new Error(`Expected success, got error: ${result.message}`);
+	}
+	return result;
+}
+
+describe("createPlayerCharacter", () => {
+	it("creates a valid player character", () => {
+		const { characters, events } = success(
+			[],
+			"Aragorn",
+			16,
+			120,
+			"green",
+			"shield",
+		);
+
+		expect(characters).toHaveLength(1);
+		expect(characters[0]).toEqual({
+			id,
+			name: "Aragorn",
+			ac: 16,
+			maxHp: 120,
+			color: "green",
+			icon: "shield",
+		});
+		expect(events).toEqual([
+			{
+				type: "PlayerCharacterCreated",
+				playerCharacterId: id,
+				name: "Aragorn",
+			},
+		]);
+	});
+
+	it("trims whitespace from name", () => {
+		const { characters } = success([], "  Gandalf  ", 12, 80);
+		expect(characters[0].name).toBe("Gandalf");
+	});
+
+	it("appends to existing characters", () => {
+		const existing: PlayerCharacter = {
+			id: playerCharacterId("pc-0"),
+			name: "Legolas",
+			ac: 14,
+			maxHp: 90,
+			color: "green",
+			icon: "eye",
+		};
+		const { characters } = success([existing], "Gimli", 18, 100, "red", "axe");
+		expect(characters).toHaveLength(2);
+		expect(characters[0]).toEqual(existing);
+		expect(characters[1].name).toBe("Gimli");
+	});
+
+	it("rejects empty name", () => {
+		const result = createPlayerCharacter([], id, "", 10, 50, "blue", "sword");
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-name");
+		}
+	});
+
+	it("rejects whitespace-only name", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"   ",
+			10,
+			50,
+			"blue",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-name");
+		}
+	});
+
+	it("rejects negative AC", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			-1,
+			50,
+			"blue",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-ac");
+		}
+	});
+
+	it("rejects non-integer AC", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			10.5,
+			50,
+			"blue",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-ac");
+		}
+	});
+
+	it("allows AC of 0", () => {
+		const { characters } = success([], "Test", 0, 50);
+		expect(characters[0].ac).toBe(0);
+	});
+
+	it("rejects maxHp of 0", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			10,
+			0,
+			"blue",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-max-hp");
+		}
+	});
+
+	it("rejects negative maxHp", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			10,
+			-5,
+			"blue",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-max-hp");
+		}
+	});
+
+	it("rejects non-integer maxHp", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			10,
+			50.5,
+			"blue",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-max-hp");
+		}
+	});
+
+	it("rejects invalid color", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			10,
+			50,
+			"neon",
+			"sword",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-color");
+		}
+	});
+
+	it("rejects invalid icon", () => {
+		const result = createPlayerCharacter(
+			[],
+			id,
+			"Test",
+			10,
+			50,
+			"blue",
+			"banana",
+		);
+		expect(isDomainError(result)).toBe(true);
+		if (isDomainError(result)) {
+			expect(result.code).toBe("invalid-icon");
+		}
+	});
+
+	it("emits exactly one event on success", () => {
+		const { events } = success([], "Test", 10, 50);
+		expect(events).toHaveLength(1);
+		expect(events[0].type).toBe("PlayerCharacterCreated");
+	});
+});