feat(frontend): CoingeckoCoinsId zod (#3329)

# Motivation

Zod for `CoingeckoCoinsId`.

# Notes

I just convert the type I need for the PR / task I'm working on in #3326
and not all the Coingecko types.

src/frontend/src/lib/types/coingecko.ts

@@ -4,8 +4,10 @@
 // *refers to curl -l https://api.coingecko.com/api/v3/coins/list
 import type { LedgerCanisterIdText } from '$icp/types/canister';
 import type { EthAddress } from '$lib/types/address';
+import type { CoingeckoCoinsIdSchema } from '$lib/validation/coingecko.validation';
+import { z } from 'zod';
 
-export type CoingeckoCoinsId = 'ethereum' | 'bitcoin' | 'internet-computer';
+export type CoingeckoCoinsId = z.infer<typeof CoingeckoCoinsIdSchema>;
 
 // We are interested only in the ERC20 <> USD on Ethereum and in the ICRC <> USD on Internet Computer, therefore not an exhaustive list.
 // *refers to curl -l https://api.coingecko.com/api/v3/asset_platforms

src/frontend/src/lib/validation/coingecko.validation.ts

@@ -0,0 +1,3 @@
+import { z } from 'zod';
+
+export const CoingeckoCoinsIdSchema = z.enum(['ethereum', 'bitcoin', 'internet-computer']);

src/frontend/src/tests/lib/validation/coingecko.validation.spec.ts

@@ -0,0 +1,39 @@
+import { CoingeckoCoinsIdSchema } from '$lib/validation/coingecko.validation';
+import { describe, expect, it } from 'vitest';
+
+describe('CoingeckoCoinsIdSchema', () => {
+	it('should pass validation for "ethereum"', () => {
+		const validData = 'ethereum';
+		expect(CoingeckoCoinsIdSchema.parse(validData)).toEqual(validData);
+	});
+
+	it('should pass validation for "bitcoin"', () => {
+		const validData = 'bitcoin';
+		expect(CoingeckoCoinsIdSchema.parse(validData)).toEqual(validData);
+	});
+
+	it('should pass validation for "internet-computer"', () => {
+		const validData = 'internet-computer';
+		expect(CoingeckoCoinsIdSchema.parse(validData)).toEqual(validData);
+	});
+
+	it('should fail validation for an unsupported coin ID', () => {
+		const invalidData = 'dogecoin';
+		expect(() => CoingeckoCoinsIdSchema.parse(invalidData)).toThrow();
+	});
+
+	it('should fail validation for a number instead of a string', () => {
+		const invalidData = 123;
+		expect(() => CoingeckoCoinsIdSchema.parse(invalidData)).toThrow();
+	});
+
+	it('should fail validation for null', () => {
+		const invalidData = null;
+		expect(() => CoingeckoCoinsIdSchema.parse(invalidData)).toThrow();
+	});
+
+	it('should fail validation for undefined', () => {
+		const invalidData = undefined;
+		expect(() => CoingeckoCoinsIdSchema.parse(invalidData)).toThrow();
+	});
+});