Merge #4358: M5: comments in an /RT /Group are one comment, with the primary's attributes (#4357)

# Conflicts:
#	crates/automation/src/comments.rs
#	crates/automation/tests/it/automation.rs
#	crates/render/src/inspect.rs
#	crates/render/src/inspect/annotations.rs
#	crates/render/src/lib.rs
#	crates/ui-egui/src/panels/comments_panel.rs

parity/acrobat-features.toml

@@ -3662,8 +3662,8 @@ milestone = "M3"
 status = "shipped"
 commands = ["comment.list"]
 tools = ["comment_list"]
-evidence = ["crates/ui-egui/tests/it/ui.rs::opening_a_pdf_shows_comments_and_bookmarks", "crates/ui-egui/tests/it/comments.rs::the_panel_posts_comments_and_replies", "crates/ui-egui/tests/it/comments.rs::page_groups_collapse_and_expand", "crates/ui-egui/tests/it/comments.rs::replies_follow_irt_references_when_names_repeat_on_every_page", "crates/engine/src/tests.rs::replies_thread_by_reference_when_names_repeat_across_pages", "crates/automation/tests/it/automation.rs::replies_thread_by_reference_when_ids_repeat_across_pages"]
-notes = "cards grouped by page with replies (threaded by the `/IRT` reference, so files whose `/NM` repeats per page, as PyMuPDF writes them, thread correctly; the header counts comments without replies, as Acrobat does), status badges, selection, reply box and an Add a comment box; page groups fold and unfold from their chevron or with Collapse/Expand all pages in the panel's \"…\" menu (a comment selected on a folded page opens its group). Groups by author, type or colour don't fold yet"
+evidence = ["crates/ui-egui/tests/it/ui.rs::opening_a_pdf_shows_comments_and_bookmarks", "crates/ui-egui/tests/it/comments.rs::the_panel_posts_comments_and_replies", "crates/ui-egui/tests/it/comments.rs::page_groups_collapse_and_expand", "crates/ui-egui/tests/it/comments.rs::replies_follow_irt_references_when_names_repeat_on_every_page", "crates/engine/src/tests.rs::replies_thread_by_reference_when_names_repeat_across_pages", "crates/automation/tests/it/automation.rs::replies_thread_by_reference_when_ids_repeat_across_pages", "crates/ui-egui/tests/it/comments.rs::a_group_is_one_comment_in_the_panel_and_on_the_page", "crates/automation/tests/it/automation.rs::a_group_lists_as_its_primary", "crates/automation/tests/it/automation.rs::a_group_member_on_another_page_is_a_comment_of_its_own", "crates/automation/tests/it/automation.rs::looping_groups_end_and_chained_groups_reach_their_primary", "crates/render/src/inspect/tests.rs::group_primaries_follow_irt_to_the_first_non_subordinate", "crates/annot/src/tests.rs::deleting_a_primary_releases_its_subordinate", "crates/engine/src/tests.rs::deleting_a_group_primary_releases_its_member_in_one_undo_step"]
+notes = "cards grouped by page with replies (threaded by the `/IRT` reference, so files whose `/NM` repeats per page, as PyMuPDF writes them, thread correctly; the header counts comments without replies, as Acrobat does), status badges, selection, reply box and an Add a comment box; page groups fold and unfold from their chevron or with Collapse/Expand all pages in the panel's \"…\" menu (a comment selected on a folded page opens its group). Groups by author, type or colour don't fold yet. Annotation groups (`/RT /Group`, ISO 32000-2 §12.5.6.2) list as one comment with the primary's author, text and colour (the subordinate's own are ignored), a reply to a subordinate joins the primary's thread, `comment_list` names the members in `group`, clicking a subordinate on the page selects the group, and Delete deletes the member clicked alone, the primary included, as Acrobat desktop does (one undo step; a subordinate left without its primary is a comment of its own and loses its `/IRT`, keeping `/RT /Group` as Acrobat does, so a full save leaves the deleted primary out; clearing redaction marks does the same for a mark's group member; Replace Text's strikeout and caret delete together). ISO 32000-2 §12.5.6.2 has deletion act on the whole group, as PDF-XChange and Foxit do on one page; Acrobat's is followed as the more practical. A group is one page's: a subordinate whose primary is on another page is a comment of its own, listed, selected, moved and deleted on its own, as Acrobat (desktop and iPad), PDF-XChange and Foxit read it. Missing: restyling a member does not restyle its group as Acrobat does, a subordinate can't be dragged, resized or reshaped on its own, and it has no hover tooltip"
 
 [[feature]]
 id = "comment.appearance-generation"
@@ -3746,8 +3746,8 @@ milestone = "M5"
 status = "shipped"
 commands = ["comment.replace"]
 tools = ["comment_add"]
-evidence = ["crates/annot/src/tests.rs::replace_text_groups_a_strikeout_and_a_caret", "crates/ui-egui/tests/it/comments.rs::replacing_text_strikes_it_and_adds_a_caret", "crates/automation/tests/it/automation.rs::drawing_comments_through_tools"]
-notes = "a caret holding the replacement, the group's primary (/IT /Replace), with the strikeout (/IT /StrikeOutTextEdit) grouped under it (/IRT, /RT /Group), as ISO 32000-2 §12.5.6.2 reads a group's text from its primary; deleting either deletes both. Missing: /RT /Group is not read yet, so the Comments panel and comment_list show the strikeout as a reply of the caret (#4357)."
+evidence = ["crates/annot/src/tests.rs::replace_text_groups_a_strikeout_and_a_caret", "crates/ui-egui/tests/it/comments.rs::replacing_text_strikes_it_and_adds_a_caret", "crates/automation/tests/it/automation.rs::drawing_comments_through_tools", "crates/automation/tests/it/automation.rs::replace_text_lists_its_replacement", "crates/annot/src/tests.rs::restyling_a_replace_text_pair_restyles_both_members", "crates/xfdf/src/tests.rs::a_replace_text_pair_survives_an_xfdf_round_trip"]
+notes = "a caret holding the replacement (/IT /Replace) is the group's primary and a strikeout (/IT /StrikeOutTextEdit) its /RT /Group subordinate (ISO 32000-2 §12.5.6.2), so the pair lists, selects and deletes as one comment with the replacement text. Groups saved by earlier builds the other way round (strikeout primary with no text) still list the caret's text, without rewriting the file. Restyling either member restyles both (colour and opacity, one undo step), and XFDF keeps both intents. Missing: moving the caret does not move the strikeout"
 
 [[feature]]
 id = "comment.insert-text"