BETA 995 re-measurement, ide-test.bat for IDE scenarios, and impexp import writes the IDE's empty folders

[KubaO]

Re-runs the documentation's BETA 983–987 measurements on BETA 995 and adds a second test runner, for scenarios that operate the IDE itself.

• scripts, test: scripts/lib/lane-runner.mjs is the add-in lane runner, shared. ide-test.bat (new, base port 9660) runs test/ide/lanes.mjs over it and exports the project first. Four lanes so far:
  • debugger: Debug.md's two defects still hold on 995.
  • export: ${SourcePath} is deleted, and the CLI refuses to repack.
  • packages: an imported package is still unticked, and one Apply keeps running the replaced package.
  • assert: Stop at a failed Assert.
• scripts: check_cli's cases move to scripts/lib/cli-cases.mjs. pdf.mjs reads the book's fonts from print.css.
• lint: noUndeclaredVariables is on, with axe and Paged declared only where they run in a page.
• impexp: import adds the empty folders the IDE always writes, to the project and to each embedded package. The Python and JS editions stay in parity.
• docs:
  • >> is arithmetic since 984.
  • As New needs a no-argument constructor (TB5121).
  • ThisCall and FastCall are added to API Declarations' Calling Conventions and the Core syntax lines.
  • LLVM-compiled code ignores Debug.Assert and skips its condition.
  • 984's FileCopy, Line Input, ReDim and #Const fixes are noted.
  • The census figure, the error-9 note, Attributes.md's applicability notes and three tbIDE notes are re-measured on 995.
• bugs:
  • New: FastCall and ThisCall delegates call as stdcall on win32.
  • New: an embedded package with no Packages folder puts 995's compiler in a crash loop.
  • New: As New refuses an all-Optional constructor.
  • New: FileCopy of an open file differs from VB6.
  • Re-run on 995: the command-line entries are unchanged, and the Forms-by-index crash needs a variable As Form.
  • Two editor entries are checked against 995's main.js.
• wip: the harness and add-in notes are re-checked on 995. A forward-slash export failure exits 0.

ide-test.bat and addin-test.bat stay outside every gate and CI, like examples.bat.