Port FieldBatchCodec and ForestCodec to ClientVersionDispatchingCodecBuilder

[CraigMacomber]

Description

Port FieldBatchCodec and ForestCodec to ClientVersionDispatchingCodecBuilder.

Reviewer Guidance

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[Copilot]

Pull request overview

This PR migrates the FieldBatchCodec and ForestCodec implementations from the older makeVersionedValidatedCodec pattern to use the newer ClientVersionDispatchingCodecBuilder pattern. This modernizes the codec infrastructure and provides better type safety and consistency with other codecs in the codebase.

Changes:

• Replaced makeFieldBatchCodec function with fieldBatchCodecBuilder constant using ClientVersionDispatchingCodecBuilder
• Replaced makeForestSummarizerCodec function with forestCodecBuilder constant using ClientVersionDispatchingCodecBuilder
• Updated all usage sites to call .build() on the codec builders instead of calling factory functions
• Updated error message regex patterns in tests to match the new JSON array format for version lists
• Changed EncodedFieldBatch export from value export to type-only export
• Added type narrowing assertions in tests where codec return types became more generic
• Added type cast in treeAlpha.ts due to loss of specific return type information

Reviewed changes

Copilot reviewed 20 out of 20 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/dds/tree/src/feature-libraries/chunked-forest/codec/codecs.ts	Refactored to use ClientVersionDispatchingCodecBuilder pattern, extracting codec logic into helper function
packages/dds/tree/src/feature-libraries/chunked-forest/codec/index.ts	Changed EncodedFieldBatch export to type-only and replaced function export with builder
packages/dds/tree/src/feature-libraries/chunked-forest/index.ts	Updated exports to use fieldBatchCodecBuilder
packages/dds/tree/src/feature-libraries/forest-summary/codec.ts	Complete refactor to use ClientVersionDispatchingCodecBuilder with ForestCodecOptions interface
packages/dds/tree/src/feature-libraries/forest-summary/index.ts	Updated exports to use forestCodecBuilder
packages/dds/tree/src/feature-libraries/forest-summary/forestSummarizer.ts	Updated to call forestCodecBuilder.build()
packages/dds/tree/src/feature-libraries/index.ts	Updated public API exports
packages/dds/tree/src/shared-tree/*.ts	Updated usage sites to call .build() on codec builders
packages/dds/tree/src/test/**/*.spec.ts	Updated tests to use new builder pattern and adjusted error message assertions