Print: Windows lists its printers and spools jobs (#847)

* Print: Windows lists its printers and spools jobs (#756)

The Print dialog's printer list comes from Win32_Printer through PowerShell's
CIM (wmic is gone from Windows 11), and jobs are spooled by the embedded
windows_print.ps1: the in-box Windows.Data.Pdf renders each sheet at the
printer's own resolution and System.Drawing.Printing carries copies,
collation, duplex and colour as the job's settings. Both run through
powershell, so the Rust code touches no Win32 API. Fixes #756, with the
printer-not-showing duplicates #160, #244, #293, #465 and #644; CIM approach
from #452. On CI a paused Generic / Text Only test printer catches the job in
its queue; a parser test keeps the script valid PowerShell.

* Print: fix the Windows await helper and render the job on CI (dry run)

Real-machine testing found [System.WindowsRuntimeSystemExtensions]::GetMethods()
failing with 'does not contain a method named GetMethods': GetMethods is an
instance method of [Type], so it is called with '.', the form the canonical
WinRT-await snippets use, not '::'. The first CI run missed it because the
end-to-end test skipped silently when the runner refused the test printer, so
the script had never actually run.

The script now honours PDFCRAFT_PRINT_DRYRUN=1: render every sheet with
Windows.Data.Pdf to PNGs in the temporary folder and print nothing. The test
runs that half unconditionally, so CI exercises the whole WinRT path —
projection, await helpers, render — on any machine, while the paused-printer
half stays best-effort and prints why it skipped. Win32_Printer enumeration
asks only for Name and Default, so a machine with nine printers waits less.

* Tests: the find-options wait in the viewer test is a deadline too

4280f83 converted the frame-count waits in this test to deadlines after the
same 12-of-15 race under a full workspace test run, but left the first wait —
the one for the 'page' matches — on the old 60-frame loop, and it flaked the
same way on PR #847's CI. Same fix: wait up to 20 s for the 15 matches, then
assert.

docs/gaps.md

@@ -22,7 +22,7 @@ update the numbers.
 | 1 | Encrypted files we write don't open in Acrobat | file format | 8–15 | [file-format-parity.md](file-format-parity.md) |
 | 2 | Rendering is borrowed and its fidelity unmeasured | feature, spec | 110–190 | [pdf-spec-parity.md](pdf-spec-parity.md) |
 | 3 | Editing existing text is fragile on real files | feature | 100–180 | [target-app-parity.md](target-app-parity.md) |
-| 4 | No printing on Windows or the web | feature, platform | 15–30 | [hardware-parity.md](hardware-parity.md) |
+| 4 | No printing on the web | feature, platform | 15–30 | [hardware-parity.md](hardware-parity.md) |
 | 5 | Chinese UI shows missing-glyph boxes in releases | localization | 6–12 | [localization-parity.md](localization-parity.md) |
 | 6 | Open-issue backlog of wrong results in shipped features | stability | 45–80 | this file |
 | 7 | OCR reads only unaccented Latin | feature | 40–75 | [file-format-parity.md](file-format-parity.md) |
@@ -97,12 +97,14 @@ update the numbers.
   how a document looks.
 - **Estimate:** 100–180 h (the longest feature pole, M7). **Doc:** [target-app-parity.md](target-app-parity.md).
 
-### 4. No printing on Windows or the web
+### 4. No printing on the web
 
-- **Missing:** a Windows spooler (and printer properties), browser printing.
-- **Evidence:** [#756](https://github.com/storytold/pdfcraft/issues/756): on Windows 11 the Print
-  dialog only saves a PDF. `crates/print/README.md`: "Not yet: Windows and web spoolers".
-- **Impact:** Windows is most of Acrobat's market. Printing is a P0 workflow.
+- **Missing:** browser printing.
+- **Evidence:** the web build has no spooler: off Windows and unix, `spool::submit` reports that
+  printing to a printer isn't available and only the print-ready PDF can be saved.
+  `crates/print/README.md`: "Not yet: the web spooler".
+- **Impact:** the web build cannot send a job to a printer; printing is a P0 workflow. Printing on
+  Windows shipped with [#756](https://github.com/storytold/pdfcraft/issues/756).
 - **Estimate:** 15–30 h. **Doc:** [hardware-parity.md](hardware-parity.md).
 
 ### 5. Chinese UI shows missing-glyph boxes in releases