Replaces the manual MarkdownChef → chunker → OverlapRefinery wiring (and
the _ChunkerCache / _apply_overlap / _group_overlap_runs / _neural_enforce_size
layer) with three pre-built chonkie.Pipeline instances dispatched by file suffix.
- Drop 'semantic' and 'neural' chunking strategies and their model pins;
RecursiveChunker is the only prose chunker. BM25/FTS5 doesn't benefit
from topical coherence.
- Drop ChunkingConfig.strategy and ChunkingConfig.threshold. No legacy
compatibility — old keys in user configs are silently ignored.
- Drop block_index / src / link / row_count / column_count metadata as not
load-bearing for keyword search.
- Drop _single_chunk short-circuit so small files still flow through the
Pipeline (preserves prose/code split for tiny multimodal markdown).
- Drop manual _apply_overlap; OverlapRefinery.refine_document handles prose
chunks inside the Pipeline, populating Chunk.context directly.
- Bump CHUNKING_PLAN_VERSION from v1 to v2 so existing indexes get
re-built cleanly on upgrade.
alt-glitch
77c10079c8