fix(vba): remove duplicate Dysflow artifact extraction

[ardelperal]

Closes #314

What was wrong

The #154 refactor lifted the three Dysflow sub-extractors (VbaFormExtractor, VbaTestManifestExtractor, VbaTestSequenceExtractor) into dysflowExportResolver, but the pre-refactor dispatch ladder in src/extraction/tree-sitter.ts was never removed. Both ran inside a single extractFromSource call, and dysflowExportResolver.detect() is true for any project carrying a Dysflow artifact — so every real export parsed each .form.txt / .report.txt / test manifest / test sequence twice per index.

Measured on the pre-fix build:

manifest | no-fw nodes=1 refs=1  ||  with-fw nodes=2 refs=2
sequence | no-fw nodes=1 refs=1  ||  with-fw nodes=2 refs=2
form     | no-fw nodes=4 refs=1  ||  with-fw nodes=8 refs=2

Deterministic node IDs collapse the duplicate nodes on insert, so what survived was the doubled parse cost plus duplicate unresolved_refs rows for every manifest entry and sequence procedure.

What changed

extract() (and its pickSubExtractor helper) is removed from dysflowExportResolver. Per-file dispatch stays in the tree-sitter.ts ladder, which is the only site that runs on every path into extraction — including the many callers that pass no frameworkNames at all (single-file re-index, library consumers, the extraction unit tests). Removing the ladder instead would have silently emptied those paths.

The resolver keeps detect() and resolve(), and its docstring now states where extraction actually lives and why re-adding an extract() here reintroduces the duplication.

Second defect fixed on the way

The removed extract() never checked the dysflowExport flag. With the framework registered, vba.dysflowExport: false still emitted the full Dysflow shape instead of the file-only node it promises. Test D pins the opt-out under that combination.

Verification

• pnpm exec vitest run vba extraction-sql-query sql-query-discovery — 72 files, 1207 passed, 1 skipped (the Windows CI leg, run locally on Windows).
• npx tsc --noEmit — clean.
• New Test D (8 cases) covers frameworkNames: ['dysflow-export'] with dysflowExport: true, the combination the real index path uses and the one nothing exercised before. Reverting only src/extraction/frameworks/dysflow-export.ts fails all 8; with the fix all 20 tests in the suite pass.