M10: recognize a scanned page when Edit is turned on for it

Acrobat's Edit on a scanned page first converts it to editable text and images.
In PdfCraft the words had to be recognized through Scan & OCR before Edit text &
images could open them. Turning Edit text & images on for a page that is a
picture (an image covering at least half of a page with no text) now runs the
recognition for that page first: once per page per window, one undoable
"Recognize text" step, with the language of the Recognize Text dialog. Pages
with text, read-only files and other tools are left alone.

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

parity/acrobat-features.toml

@@ -6516,8 +6516,8 @@ milestone = "M10"
 status = "partial"
 commands = ["edit.edit_text"]
 tools = ["text_edit"]
-evidence = ["crates/engine/tests/ocr_edit.rs::editing_an_ocr_word_covers_the_scan_and_shows_the_new_text", "crates/engine/tests/ocr_edit.rs::an_explicit_colour_is_kept_for_the_new_text", "crates/engine/tests/ocr_edit.rs::ocr_words_group_into_phrases_that_edit_in_place", "crates/engine/tests/ocr_edit.rs::a_longer_ocr_phrase_grows_rightwards", "crates/engine/tests/ocr_edit.rs::a_rewritten_ocr_phrase_keeps_its_word_widths", "crates/ui-egui/tests/ocr.rs::an_ocr_word_opens_for_editing_and_stays_open"]
-notes = "On demand, per edit: in Edit text & images, recognised text (the invisible OCR layer over a scan) is grouped into phrases (words across a word space; a wider gap such as a table cell, and each scanned line, stay separate) and opens for editing on a click. Applying draws the new text visibly in the scan's sampled ink colour (or the chosen one) and first covers the old words with the paper colour sampled around them, so the scanned word no longer shows; the phrase keeps each word's position and width and grows rightwards instead of wrapping. Still missing: Acrobat's Recognize Text output that converts a whole page to editable text at once, matching the scanned typeface (the layer's Helvetica is used), and covering on a textured or patterned background (one flat colour is used)."
+evidence = ["crates/engine/tests/ocr_edit.rs::editing_an_ocr_word_covers_the_scan_and_shows_the_new_text", "crates/engine/tests/ocr_edit.rs::an_explicit_colour_is_kept_for_the_new_text", "crates/engine/tests/ocr_edit.rs::ocr_words_group_into_phrases_that_edit_in_place", "crates/engine/tests/ocr_edit.rs::a_longer_ocr_phrase_grows_rightwards", "crates/engine/tests/ocr_edit.rs::a_rewritten_ocr_phrase_keeps_its_word_widths", "crates/ui-egui/tests/ocr.rs::an_ocr_word_opens_for_editing_and_stays_open", "crates/ui-egui/tests/ocr.rs::editing_a_scanned_page_recognizes_its_text_first_and_only_once"]
+notes = "On demand, per edit: in Edit text & images, recognised text (the invisible OCR layer over a scan) is grouped into phrases (words across a word space; a wider gap such as a table cell, and each scanned line, stay separate) and opens for editing on a click. Applying draws the new text visibly in the scan's sampled ink colour (or the chosen one) and first covers the old words with the paper colour sampled around them, so the scanned word no longer shows; the phrase keeps each word's position and width and grows rightwards instead of wrapping. Turning Edit text & images on for a scanned page (an image covering at least half of a page that has no text, once per page per window; one undoable \"Recognize text\" step) now recognizes its words first, as Acrobat's \"Converting scanned page to Editable Text and Images\" does (English only until more OCR languages exist, gap 7). Still missing: separating the photographs on the page from the lettering, matching the scanned typeface (the layer's Helvetica is used), and covering on a textured or patterned background (one flat colour is used)."
 
 [[feature]]
 id = "ocr.ocr-downsample"