feat(sink): support sink map to avro

[xxchan]

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[xxchan]

• feat(sink): support sink map to protobuf #18552
• feat(sink): support sink map to avro #18551 👈
• fix(sink): remove some todo!() with error #18550
• main

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[xxchan]

parsing nested map is not supported... so manually construct a test here...

[chenzl25]

LGTM. BTW, What's the purpose of impl MaybeData for () ?

[xxchan]

What's the purpose of impl MaybeData for () ?

@xiangjinwu 's invention:

risingwave/src/connector/src/sink/encoder/avro.rs

Lines 155 to 171 in 97a3293

	/// A trait that assists code reuse between `validate` and `encode`.
	/// * For `validate`, the inputs are (RisingWave type, ProtoBuf type).
	/// * For `encode`, the inputs are (RisingWave type, RisingWave data, ProtoBuf type).
	///
	/// Thus we impl [`MaybeData`] for both [`()`] and [`DatumRef`].
	trait MaybeData: std::fmt::Debug {
	type Out;
	fn on_base(self, f: impl FnOnce(ScalarRefImpl<'_>) -> Result<Value>) -> Result<Self::Out>;
	/// Switch to `RecordSchema` after #12562
	fn on_struct(self, st: &StructType, avro: &AvroSchema) -> Result<Self::Out>;
	fn on_list(self, elem: &DataType, avro: &AvroSchema) -> Result<Self::Out>;
	fn handle_union(out: Self::Out, opt_idx: OptIdx) -> Result<Self::Out>;
	}