fix(readarr): stop appending stray colons to the edition overview

Every line of the edition details popup was parsed as a label and a value,
so a line carrying no colon had one appended to it. A multi-line overview
therefore rendered with a spurious colon at the end of each continuation
line, and Goodreads sourced descriptions, which use CRLF, turned their
blank lines into a lone colon.

Split each line on the first colon only, leave a line without one
unlabelled, and trim the trailing carriage return so a CRLF blank line
renders as a real paragraph break.

Building the line is now a named function so its branches can be asserted
directly. Rendered text discards the carriage return, so a snapshot alone
cannot tell the trimming apart from leaving it in place.

A continuation line that happens to contain a colon is still styled as a
label. Telling those apart needs the details to be built as styled lines
rather than flattened to text and parsed back.

src/ui/readarr_ui/library/edition_details_ui_tests.rs

@@ -1,6 +1,7 @@
 #[cfg(test)]
 mod tests {
   use pretty_assertions::assert_eq;
+  use ratatui::text::Line;
   use strum::IntoEnumIterator;
 
   use crate::app::App;
@@ -9,7 +10,9 @@ mod tests {
     ActiveReadarrBlock, EDITION_DETAILS_BLOCKS,
   };
   use crate::ui::DrawUi;
-  use crate::ui::readarr_ui::library::edition_details_ui::{EditionDetailsUi, style_from_edition};
+  use crate::ui::readarr_ui::library::edition_details_ui::{
+    EditionDetailsUi, edition_detail_line, style_from_edition,
+  };
   use crate::ui::styles::{primary_style, unmonitored_style};
   use crate::ui::ui_test_utils::test_utils::render_to_string_with_app;
 
@@ -48,6 +51,64 @@ mod tests {
     assert_eq!(style, unmonitored_style());
   }
 
+  #[test]
+  fn test_edition_detail_line_splits_a_label_from_its_value() {
+    let line = edition_detail_line("Title: Test Edition", primary_style());
+
+    assert_eq!(span_contents(&line), vec!["Title:", " Test Edition"]);
+  }
+
+  #[test]
+  fn test_edition_detail_line_keeps_colons_within_a_value() {
+    let line = edition_detail_line("Release Date: 2023-01-05 15:00:00 UTC", primary_style());
+
+    assert_eq!(
+      span_contents(&line),
+      vec!["Release Date:", " 2023-01-05 15:00:00 UTC"]
+    );
+  }
+
+  #[test]
+  fn test_edition_detail_line_does_not_append_a_colon_to_a_line_without_one() {
+    let line = edition_detail_line(
+      "My name is Kvothe, pronounced nearly the same as \"quothe.\"",
+      primary_style(),
+    );
+
+    assert_eq!(
+      span_contents(&line),
+      vec!["My name is Kvothe, pronounced nearly the same as \"quothe.\""]
+    );
+  }
+
+  #[test]
+  fn test_edition_detail_line_renders_a_carriage_return_only_line_as_blank() {
+    let line = edition_detail_line("\r", primary_style());
+
+    assert_eq!(span_contents(&line), vec![""]);
+  }
+
+  #[test]
+  fn test_edition_detail_line_trims_a_trailing_carriage_return() {
+    let line = edition_detail_line(
+      "I have stolen princesses back from sleeping barrow kings.\r",
+      primary_style(),
+    );
+
+    assert_eq!(
+      span_contents(&line),
+      vec!["I have stolen princesses back from sleeping barrow kings."]
+    );
+  }
+
+  fn span_contents(line: &Line<'_>) -> Vec<String> {
+    line
+      .spans
+      .iter()
+      .map(|span| span.content.to_string())
+      .collect()
+  }
+
   mod snapshot_tests {
     use crate::models::servarr_data::readarr::modals::EditionDetailsModal;
     use crate::models::stateful_table::StatefulTable;