CVE-2026-54662: swagger-typescript-api vulnerable to code injection via unescaped `servers[0].url` in fetch http-client template

swagger-typescript-api interpolates servers[0].url directly into a TypeScript class-body field initializer of the generated fetch HttpClient (templates/base/http-clients/fetch-http-client.ejs:75), without any escaping. A malicious URL containing a " closes the string literal that initializes public baseUrl and exposes the surrounding class body to injection. The most direct exploit declares a new static field whose initializer is an async IIFE — TypeScript evaluates static field initializers at class definition time, which is at module load. A consumer who imports the generated client (or anything that transitively imports it) executes the injected code with no further interaction — no instantiation, no method call, no use of the baseUrl. The attacker controls the OpenAPI spec; the victim is whoever runs the generator and imports the result.

This is the highest-impact sink in the package: the trigger requires only a bare import of the generated module.