Add photorealistic officer portraits

docs/GODOT_4_6_MIGRATION.md

@@ -5,7 +5,7 @@ This project targets Godot 4.6 as the active editor baseline.
 ## Current Risk Profile
 
 - The project is a simple Godot 4 `Node2D` application with data-driven JSON content.
-- There are no addons, imported art assets, shaders, TileMaps, 3D physics scenes, or export presets yet.
+- There are no addons, shaders, TileMaps, 3D physics scenes, or export presets yet. The first generated portrait PNGs are plain project files and can be loaded by the dialogue UI before editor import metadata exists.
 - The current renderer is explicitly set to `gl_compatibility`, so new-project rendering defaults in Godot 4.6 should not silently change the existing project renderer.
 - `project.godot` advertises `config/features=PackedStringArray("4.6")`.
 - Godot 4.6 script UID sidecar files (`*.gd.uid`) are part of the migrated project metadata and should stay versioned.
@@ -62,6 +62,7 @@ powershell -NoProfile -ExecutionPolicy Bypass -File tools\check_godot46_readines
 - Enemy turn advances and AI acts, including damage-aware physical target selection.
 - Victory and defeat panels still appear.
 - Briefings show victory/defeat text plus first-clear reward previews, while post-battle dialogue and post-battle choices still block progression until a choice is saved.
+- Opening and post-battle dialogue can show generated officer portraits from `art/portraits`, with speaker initials only used when no portrait is available.
 - Next battle loads with saved roster, inventory, joined officers, and campaign flags.
 - New Campaign clears the save and returns to the opening scenario.