Resource-local config with Resource::withConfig()

[andrepimpao]

Summary

• Add immutable resource-local configuration overrides through Resource::withConfig().
• Introduce scoped runtimes that lazily combine the latest API configuration with resource overrides.
• Propagate effective configuration through hooks, errors, responses, entities, collections, envelopes, and cached responses.
• Document typed SDK helpers, generic overrides, precedence, resource reuse, and request mapping for version 3.1.0.

Behavior

• Resource overrides never mutate API-wide configuration or the original resource.
• Repeated calls preserve unrelated values, with later values winning for duplicate keys.
• Non-overridden values continue following later API configuration changes.
• withConfig() composes with withCache() in either order.
• Configuration values are not automatically converted into query parameters or headers.