feat: _parent context for child selector matches

[jamestexas]

Summary

• Injects _parent key into child match values when a schema node recurses into children
• Enables {{._parent.fieldName}} in child templates — chains work: {{._parent._parent.org}}
• parentAwareMatch wrapper forwards OriginProvider and GetCaptureNode so tree-sitter features (doc comments, location, write-back) continue to work
• Both processNode (MemoryStore) and collectNodes (SQLite streaming) paths wired

Test plan

• 3 tests: array fanout, 2-level nesting, no-parent-at-root
• All existing tests pass (no regressions — OriginProvider + GetCaptureNode forwarding verified)
• task lint — 0 issues
• task test — full suite green

Bead: mache-e4a559

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Adds parent-context propagation to ingestion match values so child node/file templates can reference parent fields via {{._parent.field}} (including multi-level chaining), while preserving tree-sitter-origin features by forwarding relevant interfaces.

Changes:

• Introduces parentAwareMatch wrapper to inject a _parent map into Match.Values() and forward OriginProvider + GetCaptureNode.
• Threads parent match values through both ingestion paths: processNode (MemoryStore) and collectNodes (SQLite streaming).
• Adds tests covering array fanout, 2-level nesting, and root behavior (no _parent at top level).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
internal/ingest/parent_match.go	Adds the match wrapper that injects _parent and forwards tree-sitter-related interfaces.
internal/ingest/parent_context_test.go	Adds JSON ingestion tests validating _parent access and chaining semantics.
internal/ingest/engine_records.go	Updates processNode call site for the new parent-values parameter.
internal/ingest/engine.go	Wires _parent injection into processNode and collectNodes, plus updates call sites/signatures.

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