v1.21.1-alpha -- unused-unit-in-uses fix (re-parse), tester forms CSV v6, IDE Reports menu

Extractor 1.21.1: every index must re-parse once (index --all); an older engine refuses to write a 1.21.1 index. Battery 640/640.

EXTRACTOR BUMP 1.20.0 -> 1.21.1 (1.21.0 was never released): every index re-parses once
(done 2026-10-05, 37/37 sections, 5 h 05 m).

Added

• forms-csv algorithm v6 -- a tester spreadsheet that says what to click. Edges come from
  the index first (DFM control event -> handler -> resolved call path to the routine that
  creates / shows the form); the old .pas text scan is only the fallback, and every row says
  which method found it. Each form's .dfm is read at report time for the menu / ribbon /
  action / tab path ("Ribbon: Lists > Lists Bar > Variable Names"). New columns: How to open,
  Click, Control type, Handler, Opened by, Modal, Before you start, Other ways in, Confidence
  (traced / handler-only / unresolved), Tester result. Micronite2027: "no path from MAIN"
  7 -> 5, handler-only rows with no control 1 -> 0. Guard: run_forms_csv_v6.ps1.
• IDE plugin: drag-lint > Reports. Every chart question of charts\src\Ask-Report.ps1
  (25) from the editor caret (typeat resolves the full name), run in the background; the
  chart opens in the browser and the text answer is copied as a DocInsight /// <remarks>
  block with no autodoc marker, so Auto Document preserves it. "Forms for testers (CSV)..."
  moved here from the root menu. Tests: tests\plugin\run_reports_text.ps1.

Fixed

• Ref-gap F: signature types of header-only routines are now type_use refs. An
  implementation-only free routine (1.21.0) and a NESTED routine -- local to a free routine, a
  method implementation or an interface-declared routine (1.21.1) -- emitted its symbol and
  params but no ref for its parameter or return types. An imported unit whose type appeared only
  there was reported by unused-unit-in-uses as a dead import. Guard:
  tests\autotest\run_impl_only_signature_type_uses.ps1.