Docs: installed fonts in the font menus (gaps, parity, ROADMAP, README, architecture)

gaps.md records the Windows report and its fix under real-user experience and G2; parity.md's
Text row, the ROADMAP's reliability note and the README's Text bullet say text can use any
installed font; architecture.md says when the system font scan runs.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019EjTYdt76hTG4Kh2CJFnCr

ROADMAP.md

@@ -39,7 +39,8 @@ in [docs/gaps.md](docs/gaps.md).
   - **After Effects projects can't be opened.** EffectCraft can't read `.aep` / `.aepx` files,
     and third-party After Effects plug-ins can't run.
   - **Reliability is uneven across platforms.** Early Linux users hit basic problems: viewer
-    panning, panel docking, drag-and-drop import.
+    panning, panel docking, drag-and-drop import. A Windows user found the font menus offered only
+    the bundled fonts (fixed 6 October: they list every installed font).
   - **AI tools are new.** Roto Brush's trained model (MobileSAM, M13.35) and face tracking's
     (MediaPipe Face Landmarker, M13.36) are optional downloads, not yet compared with After
     Effects.