Phase 4.4: bundled interface typeface

CHANGELOG.md

@@ -12,6 +12,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 - Ctrl+N (Cmd+N on macOS) opens a new Draft; the current Document is flushed first and stays active when saving fails or a conflict is unresolved.
 - Ctrl+P (Cmd+P on macOS) opens a temporary centered Document selector over the Writing surface, composed by a new application shell; `Escape` or a pointer click on the overlay dismisses it without forcing a save or changing the active Document, and the existing flush-or-block New Draft transition is available from inside the selector.
 - The Document selector catalogs direct-child `.txt` Files as ordered cards with previews, active-buffer overlays, and duplicate-title filename disambiguation.
+- The interface uses the bundled iA Writer Quattro variable Typeface from the first frame, so selector and feedback chrome share a stable interface typography without any download.
 - Minimal Floem application scaffold for editor-focused development.
 - Standalone local persistence boundary for UTF-8 plain-text Documents with atomic File writes.
 - Debounced autosave with synchronous shutdown flush and retryable save feedback.
@@ -21,6 +22,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/).
 - The OS window title reflects the visible Document title: the first content line, or the `Untitled` placeholder for empty Documents.
 - Un-vetoable termination (macOS Cmd+Q, system quit) preserves conflicted local content as a distinct collision-safe copy so hard quit cannot lose writing.
 - Typed Preferences domain with Appearance defaults (System Theme mapping Paper and Ink, Comfortable Writing width, zero Letter spacing, System monospace Typeface, 16px Font size, Regular Body and Bold Document-title weights), a title-heavier-than-body validation invariant, and atomic persistence; the app config now keeps session bookkeeping and Appearance in separate typed sections and migrates existing configs on their next write without losing the last-opened File (Phase 4.2).
+- Curated editor Typefaces are delivered on demand through a fixed manifest pinned to canonical upstream releases or commits (Geist Mono, JetBrains Mono, iA Writer Mono, Fira Code, Source Code Pro): SHA-256-verified downloads, an app-local cache under the platform cache directory, and retryable, offline-safe behavior — nothing is installed into the operating system (Phase 4.3).
 
 ### Changed