M7: Header & footer dialog: Shrink the page content checkbox (#2140)

The Header and Footer dialog (also opened by Bates numbering) gets a
checkbox that turns on the shrink, and its preview shows the band the
page content shrinks into. The label is translated in every catalog (the
catalog checksums in ATTRIBUTION.toml follow). The parity entry for the
shrink is shipped, with its limits: annotations and added text and images
are not moved yet.

parity/acrobat-features.toml

@@ -2433,11 +2433,11 @@ title = "Shrink document to avoid overwriting content"
 area = "C"
 tier = "P2"
 milestone = "M7"
-status = "planned"
-commands = []
-tools = []
-evidence = []
-notes = ""
+status = "shipped"
+commands = ["edit.header_footer"]
+tools = ["doc_header_footer"]
+evidence = ["crates/edit/src/tests.rs::shrink_scales_the_original_content_into_the_band_between_header_and_footer", "crates/edit/src/tests.rs::shrink_follows_the_display_space_of_a_rotated_page", "crates/edit/src/tests.rs::shrink_is_undone_by_remove_and_not_doubled_by_update", "crates/automation/tests/automation.rs::a_shrinking_header_and_footer_moves_the_page_content_out_of_their_way_through_tools", "crates/ui-egui/tests/ui_group/marks.rs::header_and_footer_dialog_can_shrink_the_page_content"]
+notes = "#2140: the page's original content is scaled evenly into the band the header and footer leave free (margin, tallest box, half the font size of clearance), centred across, in display space; Remove and Update undo it. Not moved yet: annotations (links, comments, form fields) and PdfCraft's own added text and images; not compared side by side with Acrobat's exact scale"
 
 [[feature]]
 id = "edit.watermark-add-text"