feat: simplify redirect url pattern

[zhongliang02]

Context

Currently, there's a common pattern across multiple codebases for handling redirect URLs:

const validator = new UrlValidator({
  baseOrigin: new URL(baseUrl).origin,
  whitelist: {
    protocols: ['http', 'https'],
    hosts: [new URL(baseUrl).host],
  }
})

export const callbackUrlSchema = z
  .string()
  .optional()
  .default(RECORDINGS)
  .transform((url, ctx) => {
    try {
      return validator.parse(url)
    } catch (error) {
      ctx.addIssue({
        code: z.ZodIssueCode.custom,
        message: (error as Error).message,
      })
      return z.NEVER
    }
  })
  .catch(new URL(RECORDINGS, baseUrl))

...

await router.push(callbackUrlSchema.parse(router.query[CALLBACK_URL_KEY]))

...

Changes

This PR introduces three key improvements to our URL validation and redirection process:

1. New RelUrlValidator Class
   Simplifies the creation of UrlValidator with sensible defaults
   Usage: new RelUrlValidator(origin: string | URL)
2. Enhanced UrlValidator.parse(..., fallbackUrl: string | URL)
   Adds a fallbackUrl parameter
   Eliminates the need to use callbackUrlSchema
3. parsePathname method
   Introduces UrlValidator.parsePathname(...) that can be directly assigned to window.location.pathname

Example usage

const validator = new RelUrlValidator(baseUrl)
window.location.pathname = validator.parsePathname(router.query['redirect'], '/home'))