revert models.py changes, use raw dicts without modifying codegen

Python dataclasses don't enforce types at runtime, so factory functions
can accept raw dicts without changing the generated models. This keeps
models.py identical to the codegen output.

Assisted-by: Claude Opus 4.6 (1M context)

Author: MikeGoldsmith

opentelemetry-sdk/src/opentelemetry/sdk/_configuration/models.py

@@ -759,13 +759,24 @@ class ExperimentalJaegerRemoteSampler:
     interval: int | None = None
 
 
-# Diverges from codegen: Sampler and ParentBasedSampler are typed as
-# dict[str, Any] rather than dataclasses so that unknown sampler names
-# (plugin/custom samplers) are preserved as dict keys through the config
-# pipeline. The loader stores nested fields as raw dicts anyway, so the
-# typed dataclass representation would drop unknown keys silently.
-Sampler: TypeAlias = dict[str, Any]
-ParentBasedSampler: TypeAlias = dict[str, Any]
+@dataclass
+class ParentBasedSampler:
+    root: Sampler | None = None
+    remote_parent_sampled: Sampler | None = None
+    remote_parent_not_sampled: Sampler | None = None
+    local_parent_sampled: Sampler | None = None
+    local_parent_not_sampled: Sampler | None = None
+
+
+@dataclass
+class Sampler:
+    always_off: AlwaysOffSampler | None = None
+    always_on: AlwaysOnSampler | None = None
+    composite_development: ExperimentalComposableSampler | None = None
+    jaeger_remote_development: ExperimentalJaegerRemoteSampler | None = None
+    parent_based: ParentBasedSampler | None = None
+    probability_development: ExperimentalProbabilitySampler | None = None
+    trace_id_ratio_based: TraceIdRatioBasedSampler | None = None
 
 
 @dataclass