feat: extensible type discovery

[MessiasLima]

Summary

Introduce a ServiceLoader-based extensibility mechanism that allows third-party libraries to contribute custom TypeResolvers without requiring user configuration.

Key changes:

• TypeResolverProvider SPI — New interface in dev.appoutlet.some.core with a createResolvers(strategyProvider, random) method. Implementations are discovered via java.util.ServiceLoader at runtime.
• DefaultStrategyProvider — Extracted from SomeConfig into a standalone StrategyProvider implementation backed by a strategy map, used by resolvers and the discovery pipeline.
• Refactored resolver constructors — All resolvers that previously accepted individual strategy parameters (e.g. NullableResolver(nullableStrategy), ListResolver(collectionStrategy)) now accept a StrategyProvider instead, fetching strategies via the idiomatic get<T>() extension.
• Resolver chain ordering — Discovered resolvers are inserted between NullableResolver and built-in resolvers, giving third-party types precedence over built-in ones while keeping user type factories highest and ClassResolver lowest.
• Graceful failure — Discovery errors and misbehaving providers are silently swallowed so the built-in chain always remains functional.
• autoservice-ir plugin — Added to generate META-INF/services entries from @AutoService annotations at compile time, used in test fixtures.
• Test coverage — Added ServiceLoaderDiscoveryTest, DefaultStrategyProviderTest, and test-only providers (TestTypeResolverProvider, FailingTypeResolverProvider) to verify discovery, precedence, and failure resilience. All existing resolver tests updated for the new StrategyProvider-based constructors.

Checklist

• Tests were added or updated when needed
• Documentation was updated when needed

[gemini-code-assist]

Code Review

This pull request introduces third-party resolver discovery via ServiceLoader and refactors strategy resolution by introducing DefaultStrategyProvider and passing StrategyProvider to various resolvers. Feedback focuses on improving robustness and encapsulation: specifically, making a defensive copy of _strategies in the builder, robustly iterating over ServiceLoader to handle individual provider failures, removing a redundant DefaultStrategyProvider instantiation, and restricting the visibility of strategyProvider and random properties to private in several resolvers.

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