Build the template chooser and Save as Template

The chooser completes its three tiers: bundled by template order, then
keyed user templates, then keyless boards by display name — and a
malformed user template still lists, by folder name with the loader's
own sentence on the row, never failing its neighbours. The store is
re-scanned on every presentation and on app activation, the Reveal
round trip made honest without watching a folder 09 deliberately
leaves unwatched; Reveal lives in the chooser's header and mints the
store on first press. Save as Template repeats Duplicate's sequence —
progress row with Cancel, flush, detached cancellable copy — through
the engine: mint the store, read the next user order before the copy
can count itself, Finder-ladder the name, copy excluding .git and
.trash/, then stamp the whole template: mapping on the landed copy
through updateIndex, with no bracket because the copy lives outside
every watched board. Folder attributes deliberately don't carry — the
one lock the command stays live under is the read-only-DMG one, and
carrying its mode bits would mint a read-only template in the user's
own store; the command gates instead on the real hazard, unsaved card
content. A signpost names the template only when the ladder renamed
it. One name ladder now serves Duplicate and the store.

Claude-Session: https://claude.ai/code/session_01SR4XGjmBE16ZUYWpfFHXwY

Kanban/UI/Card/CardRawSourceSession.swift

@@ -54,6 +54,25 @@ public final class CardRawSourceSession {
     /// neither blocks on the open buffer nor invalidates it … Apply stays last-writer-wins" (05).
     public var text = ""
 
+    /// The file as `enter()` read it — the baseline behind `holdsUnsavedText`, and never shown.
+    ///
+    /// `CardBodyEditSession.disk`'s counterpart, with the same job and none of its reconciliation:
+    /// this one is set once, when the outlet opens, and is not followed by a watcher reload (the
+    /// buffer above is deliberately never reconciled while it is open), so it answers exactly one
+    /// question — has the user typed anything since the file was read.
+    private var loadedText = ""
+
+    /// **Whether an open outlet is holding bytes the file does not** — the raw-source half of
+    /// 09-templates.md ▸ Save as Template's carve-out, which stays live under the
+    /// unwritable-location lock "unless an open Edit or raw-source session holds unsaved content the
+    /// suspended saves can't flush" (02-architecture.md ▸ Live-reload resilience).
+    ///
+    /// A closed outlet holds nothing (the buffer is emptied on the way out), and an open one that
+    /// has not been typed in holds nothing either — it is showing the file. Apply is the only thing
+    /// that writes it, and under the lock Apply is refused, which is precisely why a template taken
+    /// past this text would silently miss it.
+    public var holdsUnsavedText: Bool { isActive && text != loadedText }
+
     /// The alert waiting to be shown, if any — a validation refusal on Apply, or a file that could
     /// not be opened as source. Cleared by the OK that dismisses it, which returns the user to the
     /// text they were editing (05: "a failed validation keeps source mode open (toggle stays
@@ -109,6 +128,7 @@ public final class CardRawSourceSession {
         switch read() {
         case let .read(source):
             text = source
+            loadedText = source
             alert = nil
             isActive = true
             return true
@@ -175,6 +195,7 @@ public final class CardRawSourceSession {
         isActive = false
         alert = nil
         text = ""
+        loadedText = ""
     }
 }