Give the registry live display-state write-through and record-before-load

BoardRecord carries icon/iconColor; recordOpen/recordClose stamp them with the
display name, and a displayStateDelegate on the store (wired in BoardWindowHost
beside onFrameChanged) syncs all three through BoardRegistry.syncDisplayState on
every successful reload — welcome rows now wear the board's own icon and follow
in-app renames live. recordOpen now runs before the load with the folder name as
a brand-new record's provisional display name, so a first open that fails
fail-fast still lands in recents carrying the failure row-level (02's rule); an
existing record's cached name survives a failing retry, and the welcome fallback
list remains only for failures naming no record at all.

Claude-Session: https://claude.ai/code/session_01CqjXB7ASoWtbyoGod68k97

Kanban/App/AppModel.swift

@@ -531,6 +531,17 @@ public final class AppModel {
         return (lanes, cards)
     }
 
+    /// The folder name, extension stripped (01-storage-format.md § Board naming) — `displayName`'s
+    /// own fallback, and (02-architecture.md § Per-board app state) the registry record's
+    /// *provisional* display name for a board recorded before its load has run: "fail-fast means the
+    /// frontmatter can't be trusted, and the folder name is the Finder document name the user just
+    /// picked". A first successful load replaces it with the cached title through the ordinary
+    /// `displayName(of:)` path — there is no separate provisional vocabulary, just this one fallback
+    /// used a moment earlier than usual.
+    public static func folderDisplayName(of url: URL) -> String {
+        url.deletingPathExtension().lastPathComponent
+    }
+
     /// A board's display name: its `title`, falling back to the folder name sans extension
     /// (01-storage-format.md § Board naming).
     ///
@@ -540,7 +551,7 @@ public final class AppModel {
         if let title = store.snapshot.title.value, !title.isEmpty {
             return title
         }
-        return store.rootURL.deletingPathExtension().lastPathComponent
+        return folderDisplayName(of: store.rootURL)
     }
 
     // MARK: - Closing
@@ -617,7 +628,14 @@ public final class AppModel {
             recordClose: { [weak self] in
                 guard let self, let session = sessions[ref] else { return }
                 let counts = Self.liveCounts(of: session.store.snapshot)
-                boardRegistry.recordClose(id: session.recordID, laneCount: counts.lanes, cardCount: counts.cards)
+                boardRegistry.recordClose(
+                    id: session.recordID,
+                    displayName: Self.displayName(of: session.store),
+                    laneCount: counts.lanes,
+                    cardCount: counts.cards,
+                    icon: session.store.snapshot.icon.value,
+                    iconColor: session.store.snapshot.iconColor.value
+                )
             },
             clearOpenNow: { [weak self] in
                 guard let self, let session = sessions[ref] else { return }