Merge upstream/main into main preserving custom features

- Resolve all 13 merge conflicts between upstream/main and main
- Preserve full image editing suite: OBB, crop, proportional resize, arrange, and context menu actions
- Preserve text editing formatting tools: bullet/numbered lists, subscript/superscript, and line spacing
- Cleanly integrate upstream's canvas modularization, font updates, and styling changes
- Refactor arrange_image and run_edit_page_image helpers to satisfy clippy cognitive complexity limits
- All engine, edit, and UI integration test suites passing cleanly

crates/engine/src/session/editing.rs

@@ -1,4 +1,12 @@
-use super::*;
+#[cfg(test)]
+use super::check_refresh_panic;
+use super::{
+    Arc, DocId, Document, Edit, EditCtx, EditError, Label, MAX_UNDO, ObjectKind, OnceLock, RenderPool, SaveOptions, Scope, Session,
+    XFA_REMOVED_PREFIX, XFA_SCRIPTS_OFF, check_permission, comment_list, display_bytes, display_config, guard, info_fields, inspect, js, keys_after,
+    note_warnings, render_threads, run_edit, scan_colours, scope_of, shown_under_redactions, signatures_of, sync_xfa_state, undrawn_notices,
+    uses_scripts, write_incremental, xfa, xfa_sync_datasets,
+};
+use crate::{EditNotice, MarkKind};
 
 impl Session {
     /// Apply an edit. On success the previous state is undoable and the view data is refreshed.
@@ -159,13 +167,7 @@ impl Session {
         if signed && ((rewrites(&next) && !rewrites(&editor.cos)) || (next.is_modified() && next.revisions().is_empty())) {
             return Err(EditError::SignedRewrite(edit.label().to_string()));
         }
-        // What this edit drew with `?` (a value or comment text its font can't draw, stored as
-        // typed): reported, never silent (AGENTS.md §4).
-        let notices = if matches!(scope_of(&edit), Scope::Form | Scope::Comments | Scope::Full) {
-            guard(|| undrawn_notices(&editor.cos, &next)).unwrap_or_default()
-        } else {
-            Vec::new()
-        };
+        let notices = edit_notices(&edit, &editor.cos, &next);
         let previous = std::mem::replace(&mut editor.cos, next);
         let keys = keys_after(&edit).unwrap_or_else(|| editor.keys.clone());
         let previous_keys = std::mem::replace(&mut editor.keys, keys);
@@ -373,7 +375,7 @@ impl Session {
         let signatures = if doc.signatures.is_empty() { Vec::new() } else { signatures_of(&editor.cos, &bytes, &doc.trust, &doc.sig_cache) };
         doc.display = display_bytes(Some(editor), &bytes);
         doc.signatures = Arc::new(signatures);
-        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         doc.bytes = bytes;
         Ok(())
     }
@@ -431,7 +433,7 @@ impl Session {
         let signatures = if doc.signatures.is_empty() { Vec::new() } else { signatures_of(&editor.cos, &bytes, &doc.trust, &doc.sig_cache) };
         doc.display = display_bytes(Some(editor), &bytes);
         doc.signatures = Arc::new(signatures);
-        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         doc.bytes = bytes;
         doc.fonts_stale = true;
         Ok(())
@@ -458,7 +460,7 @@ impl Session {
     /// After a refresh failed: draw the display bytes it left (the original, once released),
     /// so the page still shows a document.
     pub(super) fn show_released(doc: &mut Document) {
-        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
     }
 
     /// Rebuild working bytes, inspection and renderer from the current edit state.
@@ -515,8 +517,26 @@ impl Session {
         let signatures = signatures_of(&editor.cos, &bytes, &doc.trust, &doc.sig_cache);
         doc.display = display_bytes(Some(editor), &bytes);
         doc.signatures = Arc::new(signatures);
-        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         doc.bytes = bytes;
         Ok(())
     }
 }
+
+/// What `edit`, taking `prev` to `next`, wants said: never silent (AGENTS.md §4).
+fn edit_notices(edit: &Edit, prev: &pdfcraft_cos::Document, next: &pdfcraft_cos::Document) -> Vec<EditNotice> {
+    // What it drew with `?` (a value or comment text its font can't draw, stored as typed).
+    let mut notices: Vec<EditNotice> = if matches!(scope_of(edit), Scope::Form | Scope::Comments | Scope::Full) {
+        guard(|| undrawn_notices(prev, next)).unwrap_or_default().into_iter().map(EditNotice::Undrawn).collect()
+    } else {
+        Vec::new()
+    };
+    // Pages whose own white backdrop Remove background couldn't turn back on.
+    if matches!(edit, Edit::RemoveMarks { kind: MarkKind::Background }) {
+        let pages = guard(|| pdfcraft_edit::backdrops_left_off(next)).unwrap_or_default();
+        if !pages.is_empty() {
+            notices.push(EditNotice::BackdropsLeftOff { pages });
+        }
+    }
+    notices
+}

crates/engine/src/session/files.rs

@@ -1,4 +1,8 @@
-use super::*;
+use super::{
+    Arc, CombineSource, Combined, DataFormat, DocId, EditError, Hidden, ImageResolution, LOW_RESOLUTION_PRINT_DPI, OptimizeReport, SaveOptions,
+    Session, SourceKind, SplitPart, decode_text, guard, open_source, open_source_with, optimize, print, print_raster, set_default_layer_state,
+    source_kind, writable, write_full,
+};
 
 impl Session {
     /// The page count of another PDF (Replace Pages, Insert Pages dialogs).
@@ -64,10 +68,12 @@ impl Session {
         if pdf { Ok(bytes.clone()) } else { self.convert_to_pdf(name, bytes).map(|(_, pdf)| pdf) }
     }
 
-    /// Reduce File Size: Acrobat's defaults (images above 225 ppi to 150 ppi, JPEG medium
-    /// quality; thumbnails dropped), identical resources merged, unused objects dropped, objects
-    /// packed into compressed object streams. Returns the bytes and how many objects were
-    /// merged. The open document is not changed (Acrobat saves the reduced copy as a new file).
+    /// Reduce File Size: Acrobat's defaults (colour and grey images above 225 ppi to 150 ppi,
+    /// JPEG medium quality; black-and-white averaged down to 300 ppi above 450 ppi, and stored as
+    /// CCITT Group 4 whenever smaller; thumbnails dropped), identical resources merged, unused
+    /// objects dropped, objects packed into compressed object streams. Returns the bytes and how
+    /// many objects were merged. The open document is not changed (Acrobat saves the reduced copy
+    /// as a new file).
     pub fn reduced_bytes(&self, id: DocId) -> Result<(Arc<Vec<u8>>, usize), EditError> {
         let (bytes, report) = self.optimized_bytes(id, &optimize::Settings::default(), &[])?;
         Ok((bytes, report.merged))

crates/engine/src/session/save.rs

@@ -1,4 +1,7 @@
-use super::*;
+use super::{
+    Arc, DocId, EditError, Keys, OpenError, RecoverySnapshot, RenderPool, SaveOptions, Session, SignOptions, TrustStore, display_bytes,
+    display_config, guard, render_threads, signatures_of, writable, write_full, write_incremental, xfa_sync_datasets,
+};
 
 impl Session {
     /// The bytes to write for Save: an incremental update of the file as opened/last saved,
@@ -167,7 +170,7 @@ impl Session {
         {
             doc.config.reading_colors = old.config.reading_colors;
             doc.config.hide_comments = old.config.hide_comments;
-            doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+            doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         }
         // Caches keyed by the edit generation (edit lines, images, measurements) must see a new
         // one; there is nothing new to autosave.
@@ -246,7 +249,7 @@ impl Session {
             let signatures = if doc.signatures.is_empty() { Vec::new() } else { signatures_of(&editor.cos, &doc.bytes, &doc.trust, &doc.sig_cache) };
             doc.display = display_bytes(Some(editor), &doc.bytes);
             doc.signatures = Arc::new(signatures);
-            doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+            doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         }
     }
 

crates/engine/src/session/view.rs

@@ -1,4 +1,7 @@
-use super::*;
+use super::{
+    Arc, BookmarkPage, BookmarkRow, DocId, Document, EditError, LayerOp, OpenError, ReadingColors, RenderConfig, RenderPool, Session, SummarySort,
+    apply_layer_state, comment_summary, display_config, local_utc_offset, outline_rows, parse_ymd, render_threads, use_layer_choices,
+};
 
 impl Session {
     pub fn new() -> Self {
@@ -243,7 +246,7 @@ impl Session {
             return false;
         }
         doc.config.hide_comments = hide;
-        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         doc.generation += 1;
         true
     }
@@ -256,7 +259,7 @@ impl Session {
             return false;
         }
         doc.config.reading_colors = colors;
-        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), doc.config.clone());
+        doc.renderer = RenderPool::new(doc.display.clone(), render_threads(), display_config(&doc.config));
         doc.generation += 1;
         true
     }