refactor endpoint bindings/middleware

[lucix-aws]

Refactor endpoint parameter bindings and middleware:

• A single function bindEndpointParams now handles bindings universally, which will allow us to reuse for auth in s3/eventbridge
  • bindEndpointParams delegates to the operation input struct to handle contextParam staticContextParam bindings.
• Refactored how builtin bindings are exposed to be more streamlined, they're now registered in GoIntegration.
• Refactored endpoint v2 resolution to be a single middleware per service.
• Introduced SmithyGoTypes and GoStdlibTypes symbol constants to remove the need to duplicate calls to SymbolUtils.createValueSymbolBuilder(name[, dep]).build() everywhere