docs: factual-drift pass + i2c option docs (#47, #48)

Fix documentation drift (each claim verified against code): theme count
21→24; waybar whole-swap lists (waybar.css=5 incl. neon-glass vs
waybar.jsonc parity=4 + boreal); idle "suspend 30"→"15 min battery-only";
Tailscale sudo→operator; hosts/live.nix "No installer yet" header; link
docs/MIGRATION.md + fix its placeholder URL; README layout tree
(+doctor/control-center/battery-notify); OVERRIDES swappy→satty; document
always-on home pieces. String fixes: keybind cheatsheet
nmtui→networkmanager_dmenu; complete nomarchy-menu usage string
(+doctor/firmware/controlcenter/rollback). Add README rows for
nomarchy.hardware.i2c.* (#48) — closes checks.option-docs.

Implemented by a worktree agent; diff reviewed and cherry-picked.
Verified V0 (flake check) + checks.option-docs green + V1 (HM build).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

docs/MIGRATION.md

@@ -88,7 +88,8 @@ before anything touches the running system.
 git clone https://git.bemagri.xyz/bernardo/nomarchy.git ~/nomarchy-migrate
 cd ~/nomarchy-migrate
 # Or start from the downstream template:
-#   nix flake init -t github:.../nomarchy   (produces flake.nix/system.nix/home.nix/…)
+#   nix flake init -t "git+https://git.bemagri.xyz/bernardo/nomarchy.git?ref=v1"
+#   (produces flake.nix/system.nix/home.nix/…)
 ```
 
 A Nomarchy downstream flake owns exactly five files. Assemble them: