feat(terminal): themed Kitty when OpenGL < 4.3 (#95)

Ghostty needs OpenGL 4.3; older GPUs (Intel HD 4000) top out at 4.2.
Installer probes glxinfo and writes settings.terminal=kitty into
theme-state when below the floor. modules/home/kitty.nix enables Kitty
with the same palette, mono font, and opacity as Ghostty so the fallback
still looks like Nomarchy.

Default machines stay Ghostty-only (no kitty in the HM closure). Doctor
and calendar still invoke Ghostty by class — V3 on Acer for SUPER+Return.

Verified: V0 flake check; installer-safety; HM with terminal=kitty builds
themed kitty.conf + TERMINAL=kitty; default template has no kitty bin.

agent/JOURNAL.md

@@ -19,6 +19,19 @@ Template:
 
 ---
 
+## 2026-07-15 — #95: themed Kitty when OpenGL < 4.3 (this commit)
+- **Task:** Bernardo: when GL &lt; 4.3 automatically add kitty — and theme it.
+- **Did:** `modules/home/kitty.nix` themes Kitty from theme-state (same
+  palette/font/opacity as Ghostty); enables when `nomarchy.terminal` is
+  kitty or `nomarchy.kitty.enable`. Installer runs `glxinfo` (mesa-demos on
+  PATH) and, if OpenGL &lt; 4.3, writes `settings.terminal = "kitty"` (+
+  `terminalReason`) into theme-state. Docs/REQUIREMENTS + README rows.
+- **Verified:** V0 flake check; HM gen with `settings.terminal=kitty` builds
+  — kitty.conf has Boreal colors, `TERMINAL=kitty`, Hyprland `$terminal=kitty`;
+  default template HM has ghostty and **no** kitty package.
+- **Pending:** V3 Acer install; doctor/calendar still hardcode ghostty.
+- **Next suggestion:** #123 (HM pre-activate dconf) — still highest install pain.
+
 ## 2026-07-15 — docs/REQUIREMENTS.md (OpenGL floor + disk planning)
 - **Task:** Bernardo: why Acer lacks OpenGL 4.3; start documenting minimum
   system requirements including storage (Nix store + snapshots).