M10: print from the web build through the browser's print dialog (gap 4) (#1243)

* Gates: fix two clippy failures on main

- ocr_ui: "Also recognize pages that already have text" used egui's own
  checkbox, which clippy.toml disallows (#1184 landed beside #1173);
  use widgets::checkbox like every other box.
- camera_edges: Rust 1.97's manual_range_contains; the rewrite keeps the
  old answer for a NaN angle (false) with an is_finite check.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019ojKsSCHWk2AuyDTFMHCd7

* M10: print from the web build through the browser's print dialog (gap 4)

The web build had no printer: spool::submit refuses on wasm, so Print
could only download the print-ready PDF. Now its Print dialog offers
"Browser's print dialog" (the default there), which reaches every
printer the operating system knows.

- web_print: PdfCraft draws the print-ready PDF's sheets itself
  (engine Exporter), one sheet a frame since wasm has no threads:
  300 dpi up to 100 sheets, 200 up to 300, 150 up to 1,000, at most
  64 MP a sheet and 1 GiB of PNGs a job. The PNGs become blob URLs
  and print from a hidden srcdoc iframe, one sheet per page, margin 0.
- Chromium prints every page at the default @page size, so a sheet of
  the paper's size turned sideways is rotated 90 degrees CCW onto it
  (as drivers do); other sizes get named @page rules.
- Copies, two-sided and colour are greyed out (the browser's dialog
  sets them). If print() is refused (e.g. a sandboxed frame), the
  print-ready PDF downloads instead, with the reason.
- pdfcraft-print stays free of web APIs; six new strings in all 20
  catalogs (ATTRIBUTION hashes refreshed); docs and parity updated,
  gap 4 closed.

Verified in headless Chromium against a trunk build: three sheets at
300 dpi, the landscape sheet turned, no blank trailing page, and the
download fallback. Firefox and Safari not yet tried.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019ojKsSCHWk2AuyDTFMHCd7

---------

Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>

parity/acrobat-features.toml

@@ -7894,8 +7894,8 @@ milestone = "M10"
 status = "shipped"
 commands = ["print.dialog"]
 tools = ["doc_print", "printers"]
-evidence = ["crates/ui-egui/tests/print.rs::print_dialog_lays_out_sheets_and_saves_a_pdf", "crates/engine/src/tests.rs::printing_lays_out_sheets_that_render"]
-notes = "⌘P; settings and live sheet preview"
+evidence = ["crates/ui-egui/tests/print.rs::print_dialog_lays_out_sheets_and_saves_a_pdf", "crates/engine/src/tests.rs::printing_lays_out_sheets_that_render", "crates/ui-egui/src/web_print.rs::a_job_draws_every_sheet_at_its_planned_resolution_then_builds_the_page", "crates/ui-egui/src/web_print.rs::the_print_page_turns_sideways_sheets_names_other_sizes_and_ends_without_a_blank_page"]
+notes = "⌘P; settings and live sheet preview; on the web the same dialog prints through the browser's print dialog"
 
 [[feature]]
 id = "print.printer-selection"
@@ -7906,8 +7906,8 @@ milestone = "M10"
 status = "shipped"
 commands = ["print.dialog"]
 tools = ["printers", "printer_options", "doc_print"]
-evidence = ["crates/print/src/tests.rs::spooler_arguments_and_printer_list", "crates/print/src/tests.rs::driverless_printers_join_the_list_without_a_queue", "crates/print/src/tests.rs::windows_printers_carry_one_default_and_keep_their_names", "crates/print/src/tests.rs::printer_options_come_from_the_ppd", "crates/print/src/tests.rs::printer_option_defaults_and_job_arguments", "crates/ui-egui/tests/print.rs::print_dialog_shows_the_printer_driver_options", "crates/ui-egui/tests/print.rs::printers_listed_in_the_background_preselect_the_default_unless_one_was_picked"]
-notes = "CUPS queues via lpstat -p -d and driverless destinations without a queue via lpstat -e; on Windows the queues and the default come from Win32_Printer (PowerShell CIM) and jobs are rendered with Windows.Data.Pdf and spooled through shared craft-print at each sheet's physical size and orientation, with bounded raster resolution up to 600 dpi (not vector passthrough); the printer list and submission run on workers without a console window. Native Windows regression execution is pending; Save as PDF on every platform. Properties…: on CUPS the driver's own PPD job options (tray, paper type, finishing …, not installable options or what the dialog sets) for this job, sent as lp -o; on Windows the driver's Printing Preferences window (printui), saved as that printer's per-user defaults rather than per job"
+evidence = ["crates/print/src/tests.rs::spooler_arguments_and_printer_list", "crates/print/src/tests.rs::driverless_printers_join_the_list_without_a_queue", "crates/print/src/tests.rs::windows_printers_carry_one_default_and_keep_their_names", "crates/print/src/tests.rs::printer_options_come_from_the_ppd", "crates/print/src/tests.rs::printer_option_defaults_and_job_arguments", "crates/ui-egui/tests/print.rs::print_dialog_shows_the_printer_driver_options", "crates/ui-egui/tests/print.rs::printers_listed_in_the_background_preselect_the_default_unless_one_was_picked", "crates/ui-egui/src/web_print.rs::resolution_falls_with_the_sheet_count_and_long_jobs_are_refused", "crates/ui-egui/src/web_print.rs::large_sheets_are_drawn_within_the_pixel_cap_and_bad_sizes_are_refused", "crates/ui-egui/src/web_print.rs::a_sink_error_or_a_page_that_isnt_there_stops_the_job"]
+notes = "CUPS queues via lpstat -p -d and driverless destinations without a queue via lpstat -e; on Windows the queues and the default come from Win32_Printer (PowerShell CIM) and jobs are rendered with Windows.Data.Pdf and spooled through shared craft-print at each sheet's physical size and orientation, with bounded raster resolution up to 600 dpi (not vector passthrough); the printer list and submission run on workers without a console window. Native Windows regression execution is pending; Save as PDF on every platform. Properties…: on CUPS the driver's own PPD job options (tray, paper type, finishing …, not installable options or what the dialog sets) for this job, sent as lp -o; on Windows the driver's Printing Preferences window (printui), saved as that printer's per-user defaults rather than per job. On the web: \"Browser's print dialog\" (the default there) reaches the system's printers through the browser; PdfCraft draws the sheets itself (300 dpi up to 100 sheets, 200 up to 300, 150 up to 1,000; at most 64 megapixels a sheet and 1 GiB a job) and prints them from a hidden iframe, one per printed page, a landscape sheet among portrait ones turned onto the paper; copies, two-sided and colour are chosen in the browser's dialog; a browser that refuses to print gets the print-ready PDF as a download. Checked in headless Chromium, not yet in Firefox or Safari; pictures, not vectors; sheets of another paper size print at their own size only where the browser honours named @page sizes (Chromium doesn't)"
 
 [[feature]]
 id = "print.copies-collate"