fix(ui): Add text places a box on a picture and beside a paragraph again

With Add text, the page router's hits included Edit text's pictures and paragraph edges, which
nothing acts on with Add text, and Add text starts a box only where nobody owns the press: on a
scanned page (a picture filling it) no click placed a box, a click within a paragraph's edge
grip beside it did nothing, and the cursor over a picture was the hand. Add text now has only
the paragraphs' bodies, over their text, where it finishes the box being typed (over_source).

New test add_text_places_a_box_on_a_picture_and_beside_a_paragraph, seen failing on the
previous commit. From CodeRabbit's review of #5300.

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

crates/ui-egui/src/canvas.rs

@@ -1433,11 +1433,18 @@ impl PageHits<'_> {
                 .filter(|e| !e.has_changes())
                 .and_then(|e| lines.get(e.block))
                 .map(|l| xf.user_rect(info, page, l.rect.map(|v| v as f32)).expand(2.0));
+            // Add text acts on the page's paragraphs only over their text (it finishes the box
+            // being typed there): not on pictures, nor beside a paragraph, where a click starts
+            // a new box.
+            let edit_text = tool == QuickTool::EditText;
+            let body = |h: &crate::page_router::Hit| {
+                matches!(h.owner, crate::page_router::Owner::Paragraph { part: crate::page_router::ParagraphPart::Body, .. })
+            };
             (
-                crate::edit_text_ui::picture_hit(xf, page, info, images, view, p),
-                crate::edit_text_ui::hit(xf, info, page, lines, open.map(|e| e.block), p),
-                (tool == QuickTool::EditText).then(|| crate::object_ui::hit(view, xf, info, page, frame, p)).flatten(),
-                crate::edit_text_ui::picture_handle_hit(clip, xf, page, info, images, view, p),
+                edit_text.then(|| crate::edit_text_ui::picture_hit(xf, page, info, images, view, p)).flatten(),
+                crate::edit_text_ui::hit(xf, info, page, lines, open.map(|e| e.block), p).filter(|h| edit_text || body(h)),
+                edit_text.then(|| crate::object_ui::hit(view, xf, info, page, frame, p)).flatten(),
+                edit_text.then(|| crate::edit_text_ui::picture_handle_hit(clip, xf, page, info, images, view, p)).flatten(),
             )
         } else {
             (None, None, None, None)

crates/ui-egui/tests/it/editing.rs

@@ -3935,6 +3935,42 @@ fn editing_existing_images_on_the_page() {
     check_existing_artwork("picture.png", png);
 }
 
+/// Add text places a box with a click anywhere off its own boxes: on a scanned page (one picture
+/// filling it) too, and just beside a paragraph, where Edit text would rewrap it.
+#[test]
+fn add_text_places_a_box_on_a_picture_and_beside_a_paragraph() {
+    let mut png = Vec::new();
+    image::RgbImage::from_pixel(80, 40, image::Rgb([200, 40, 40])).write_to(&mut std::io::Cursor::new(&mut png), image::ImageFormat::Png).unwrap();
+    let mut h = Harness::builder().with_size(egui::vec2(1400.0, 900.0)).build_eframe(move |_cc| {
+        let mut app = PdfCraftApp::new();
+        app.set_option("language", "en").unwrap();
+        app.open_bytes("picture.png", None, png.clone()).expect("opens");
+        app
+    });
+    h.run_steps(4);
+    h.state_mut().quick_tool = pdfcraft_ui_egui::QuickTool::AddText;
+    h.run_steps(2);
+    let c = h.state().views[0].page_screen_rect(0).expect("on screen").center();
+    h.hover_at(c);
+    h.run_steps(2);
+    assert_eq!(h.output().platform_output.cursor_icon, egui::CursorIcon::Text, "the I-beam over the picture");
+    click_at(&mut h, c);
+    assert!(h.state().views[0].content.draft.is_some(), "a click on the picture starts a text box");
+
+    let mut h = harness(2, |_| {});
+    h.state_mut().quick_tool = pdfcraft_ui_egui::QuickTool::AddText;
+    h.run_steps(2);
+    let id = h.state().views[0].id;
+    let block = h.state().session.get(id).unwrap().text_blocks(0)[0].clone();
+    let r = h.state().views[0].page_screen_rect(0).expect("on screen");
+    let k = r.width() / 200.0;
+    // 6 px left of the text: 4 px past its box, within a closed paragraph's edge grip in Edit text.
+    let beside = egui::pos2(r.left() + block.rect[0] as f32 * k, r.top() + (300.0 - ((block.rect[1] + block.rect[3]) / 2.0) as f32) * k)
+        - egui::vec2(6.0, 0.0);
+    click_at(&mut h, beside);
+    assert!(h.state().views[0].content.draft.is_some(), "a click beside the paragraph starts a text box");
+}
+
 #[test]
 fn dragging_the_rotate_knob_turns_a_page_image() {
     let mut png = Vec::new();