antMatchers that matches any beginning of path

You have to use absolute pattern, see AntPathMatcher:

Note: a pattern and a path must both be absolute or must both be relative in order for the two to match. Therefore it is recommended that users of this implementation to sanitize patterns in order to prefix them with “https://stackoverflow.com/” as it makes sense in the context in which they’re used.

Your modified and simplified configuration:

@Override
protected void configure(HttpSecurity http) throws Exception {
    http
        .sessionManagement()
            .sessionCreationPolicy(SessionCreationPolicy.STATELESS)
            .and()
        .csrf().disable()
        .authorizeRequests()
            .antMatchers(HttpMethod.POST, "/**/authenticate").permitAll()
            .antMatchers(HttpMethod.GET, "/**/get-public-key").permitAll()
            .antMatchers(HttpMethod.OPTIONS, "/**").permitAll()
            .anyRequest().authenticated();
}