hud chrome: remove Map window, pin top bar, dockable left/right panels (v0.5.0)

AGENTS.md

@@ -76,6 +76,7 @@ history/
         ├── NationPanel.tsx  # a nation's stats/territory/diplomacy dossier
         ├── ActionPanel.tsx  # tabs: Action / Diplomacy / Advisor + pending-queue list (per-item trash button + confirm dialog) + "Jump forward"
         ├── EventFeed.tsx    # scrolling event log (newest first)
+        ├── FloatingWindow.tsx # the HUD window primitive — free-floating (draggable, position persisted), or `pinned` (fixed top-center bar), or `dock`ed (full-height left/right column); renders dock controls when `onDockChange` is set
         ├── StatBar.tsx
         └── ui/              # 14 shadcn/ui primitives
 ```
@@ -142,6 +143,15 @@ history/
   the player is allied with the first other nation (by key order in the `nations` record), and the
   date advances 2 days. Unit + e2e assertions rely on these exact values, so keep the stub
   deterministic.
+- **HUD layout.** The game screen is a full-viewport map (z-0) with `FloatingWindow` overlays. The
+  top bar is **pinned** — a fixed, non-movable bar centered at the top a few px down (it re-centers
+  on resize and always floats above the other windows). The **dossier / event-feed / action**
+  panels are free-floating by default (the same first-run positions as before) but can each be
+  **docked** into a full-height left or right pane; the choice is persisted in `localStorage`
+  (`history.floatwin.v1.dock`) and restored on reload, so the default "float" reproduces the
+  original layout until the user docks something. The **legend** stays a small floating widget (not
+  dockable). There is **no "Map" window** — the map is zoomed/panned directly (wheel/trackpad +
+  drag).
 - Styling: Tailwind utility classes + shadcn/ui only; dark "command-center" theme (slate bg, amber
   primary, cyan accent). No CSS beyond the Tailwind import in `src/index.css`.