Denial is not absence — detection learns the unverifiable answer 06 ruled for it

Claude-Session: https://claude.ai/code/session_014PtZdPwqZuqEDLc6wZMtEy

Kanban/App/AppModel.swift

@@ -326,10 +326,12 @@ public final class AppModel {
     ///   native undo runs". The absent git state *is* the tier test; nothing here reads a flag.
     /// - **Mode `git`** (Pro only — no other tier composes a git state) — the git provider: undo as
     ///   forward restore commits over HEAD's first-parent ancestry (06).
-    /// - **Mode `none` and mode `repoNested` alike** — the **native stack**, exactly as in the free
-    ///   tier. "Boards without app-managed git — repo-nested included — bind 13-native-undo.md's
-    ///   native stack in **every** tier" (03-board-ui.md ▸ Toolbar ▸ Catalog, re-ruled 2026-07-31
-    ///   twice; 12 ▸ The provider seam; 13's header).
+    /// - **Mode `none`, `repoNested`, and `unverifiable` alike** — the **native stack**, exactly as
+    ///   in the free tier. "Boards without app-managed git — repo-nested included — bind
+    ///   13-native-undo.md's native stack in **every** tier" (03-board-ui.md ▸ Toolbar ▸ Catalog,
+    ///   re-ruled 2026-07-31 twice; 12 ▸ The provider seam; 13's header). `unverifiable` joins the
+    ///   same branch structurally — a denial can never be told apart from a repository actually
+    ///   being there, so it takes `repoNested`'s posture, undo included (06 ▸ Rules ▸ Detection).
     ///
     /// **The repo-nested no-undo case is gone** (re-ruled 2026-07-31): 06's leave-strictly-alone
     /// stance "concerns *git*, and this stack never touches git — memory-only, journal-free,
@@ -357,7 +359,7 @@ public final class AppModel {
         guard let git else { return NativeHistoryProvider() }
         switch git.mode {
         case .git: return GitHistoryProvider(boardRoot: store.rootURL)
-        case .none, .repoNested: return NativeHistoryProvider()
+        case .none, .repoNested, .unverifiable: return NativeHistoryProvider()
         }
     }