docs: REQUIREMENTS.md — OpenGL 4.3 floor, disk/RAM planning

Acer M5-481T fails Ghostty because Ivy Bridge HD 4000 tops out at
OpenGL 4.2 in Mesa; Ghostty needs 4.3 — a generation ceiling, not a
missing driver. Document that plus UEFI/x86_64, RAM, and storage floors
(Nix store generations + BTRFS snapper + hibernate swap≈RAM). Linked
from README, docs map, HARDWARE.md; #95 points here.

docs/HARDWARE.md

@@ -3,6 +3,10 @@
 How Nomarchy enables CPUs, GPUs, laptops, firmware, and peripherals — and
 what to do when your machine is not in the happy path.
 
+**Minimum bar** (OpenGL, RAM, disk, UEFI): [`REQUIREMENTS.md`](REQUIREMENTS.md)
+— read that before calling a machine “unsupported”; this file is the
+enablement stack and quirk list.
+
 > **Queue:** [`agent/BACKLOG.md`](../agent/BACKLOG.md) (PROPOSED › Hardware
 > product). Product framing: [`VISION.md`](VISION.md) § A. Design history:
 > [`ROADMAP.md`](ROADMAP.md). Docs map: [`README.md`](README.md).