M11: merge image fragments, and the Standard and Mobile optimizer presets (closes #1783) (#1784)

* M11: merge image fragments, and the Standard and Mobile optimizer presets

Some PDF printers draw a page picture as thousands of images one pixel row
high (one real page: 3,300 strips, 4.3 MB). The optimizer works image by
image, a one-row image can't be resampled, and every JPEG strip carries its
own headers, so Reduce File Size saved 2 bytes on it.

- pdfcraft-optimize `fragments` (Settings::merge_fragments, on by default):
  runs of `q … cm /Im Do Q` drawing upright 8-bit grey or RGB images in one
  colour space, sharing their left and right edges and stacked edge to edge
  (at least four, nothing else drawn between them; or, failing that, the
  rows drawn one under the other up to a gap) become one lossless image at
  their finest resolution. The image settings then resample it, and Clean
  Up drops the strips. A page whose content can't be read back exactly is
  left alone.
- Presets as in Acrobat's Settings menu: Standard (Reduce File Size's
  choices) and Mobile (images above 144 ppi to 96 ppi, JPEG high). The PDF
  Optimizer dialog has a Settings menu (Custom once an option changes) and
  a Merge image fragments box; doc_optimize takes preset and
  merge_fragments and reports merged_images and fragments_merged.
- A progress stage for the merge; four new strings in all 21 catalogs.

On the real page: Standard/Reduce 4.3 MB → 231 KB, Mobile → 161 KB, with
a rendering closer to the original than Acrobat's Mobile result (147 KB).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* Refresh catalog hashes after merging main

---------

Co-authored-by: magdale76 <16279778+magdale76@users.noreply.github.com>
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>

parity/acrobat-features.toml

@@ -7225,7 +7225,7 @@ status = "shipped"
 commands = ["optimize.reduce"]
 tools = ["doc_reduce"]
 evidence = ["crates/ui-egui/tests/create.rs::reduce_file_size_writes_a_compact_copy", "crates/ui-egui/tests/create.rs::reduce_file_size_saves_nothing_when_the_file_is_already_small", "crates/engine/src/tests.rs::create_and_reduce", "crates/automation/tests/automation.rs::creating_and_reducing_through_tools", "crates/automation/tests/automation.rs::optimizing_through_tools", "crates/optimize/tests/optimize.rs::an_identity_decode_array_does_not_stop_reduce"]
-notes = "images above 225 ppi to 150 ppi JPEG medium, thumbnails dropped, resources merged, object streams; scanner images with the default decode array are included; a copy that isn't smaller is not saved (\"already as small as it can be made\"); runs in the background with a progress bar and Cancel"
+notes = "images above 225 ppi to 150 ppi JPEG medium (after merging page pictures printed as one-pixel strips into one image), thumbnails dropped, resources merged, object streams; scanner images with the default decode array are included; a copy that isn't smaller is not saved (\"already as small as it can be made\"); runs in the background with a progress bar and Cancel"
 
 [[feature]]
 id = "optimize.compatibility-level"
@@ -7248,8 +7248,8 @@ milestone = "M11"
 status = "partial"
 commands = ["optimize.advanced"]
 tools = ["doc_optimize"]
-evidence = ["crates/ui-egui/tests/create.rs::the_pdf_optimizer_dialog_saves_an_optimized_copy", "crates/automation/tests/automation.rs::optimizing_through_tools", "crates/ui-egui/src/optimize_ui.rs::the_progress_card_shows_the_stage_and_cancels", "crates/engine/src/tests.rs::an_optimize_job_reports_its_stages_and_can_be_cancelled", "crates/optimize/tests/optimize.rs::images_and_forms_nothing_draws_are_dropped", "crates/automation/tests/automation.rs::a_deleted_image_is_not_kept_by_reduce_or_optimize"]
-notes = "Images, Discard Objects, Discard User Data, Clean Up (also drops images and forms the pages list but never draw, such as deleted images); runs in the background with a progress bar (per image) and Cancel; no Fonts or Transparency panels, no space audit"
+evidence = ["crates/ui-egui/tests/create.rs::the_pdf_optimizer_dialog_saves_an_optimized_copy", "crates/automation/tests/automation.rs::optimizing_through_tools", "crates/ui-egui/src/optimize_ui.rs::the_progress_card_shows_the_stage_and_cancels", "crates/engine/src/tests.rs::an_optimize_job_reports_its_stages_and_can_be_cancelled", "crates/optimize/tests/optimize.rs::images_and_forms_nothing_draws_are_dropped", "crates/automation/tests/automation.rs::a_deleted_image_is_not_kept_by_reduce_or_optimize", "crates/ui-egui/tests/create.rs::the_pdf_optimizer_dialog_picks_a_preset", "crates/automation/tests/automation.rs::a_page_printed_in_strips_gets_small_through_tools", "crates/optimize/tests/optimize.rs::the_mobile_preset_makes_a_printed_page_small"]
+notes = "Settings menu with the Standard and Mobile presets (Custom once an option changes; doc_optimize preset), Images (with Merge image fragments: a page picture drawn as one-pixel strips, as some PDF printers write it, is put back together so it can be resampled), Discard Objects, Discard User Data, Clean Up (also drops images and forms the pages list but never draw, such as deleted images); runs in the background with a progress bar (per image) and Cancel; no Fonts or Transparency panels, no saved custom presets, no space audit"
 
 [[feature]]
 id = "optimize.downsample-images"
@@ -7260,8 +7260,8 @@ milestone = "M11"
 status = "partial"
 commands = ["optimize.advanced"]
 tools = ["doc_optimize"]
-evidence = ["crates/optimize/tests/optimize.rs::images_are_measured_where_drawn_and_downsampled", "crates/optimize/tests/optimize.rs::settings_choose_what_happens", "crates/automation/tests/automation.rs::optimizing_through_tools"]
-notes = "colour and grayscale, bicubic, effective resolution measured where drawn; monochrome not yet"
+evidence = ["crates/optimize/tests/optimize.rs::images_are_measured_where_drawn_and_downsampled", "crates/optimize/tests/optimize.rs::settings_choose_what_happens", "crates/automation/tests/automation.rs::optimizing_through_tools", "crates/optimize/tests/optimize.rs::a_page_picture_printed_as_one_pixel_strips_is_merged_into_one_image", "crates/optimize/tests/optimize.rs::images_that_do_not_tile_a_picture_are_left_alone"]
+notes = "colour and grayscale, bicubic, effective resolution measured where drawn; image fragments stacked edge to edge are merged first (side-by-side tiles not yet); monochrome not yet"
 
 [[feature]]
 id = "optimize.recompress-images"