docs: changelog for v0.52.3

Author: ShawnMcCool

CHANGELOG.md

@@ -11,6 +11,14 @@ renames that section on tag and the release workflow extracts it.
 
 ## [Unreleased]
 
+### New
+
+- The deck page for a netdeck now shows a **variant matrix** — every other list of the same archetype side by side, best finishes first, with each card the pilots disagree on as a row. Cells show how many more or fewer copies each list plays compared with the one you're viewing, so you can see at a glance where your list stands apart from the field, what the top finishers did differently, and how much the manabases and sideboards vary.
+
+### Improved
+
+- Netdeck pages now show the deck's **mana curve** beside the crafting summary, and cards you're missing copies of are tinted in the decklist so the gaps stand out while you read.
+
 ## v0.52.2 — 2026-07-11
 
 ### New