hypr: make the per-host config lookup case-insensitive

The hosts files were written capitalized (Rutherford.lua, Chester.lua)
but the require uses the hostname exactly as `hostname` prints it —
lowercase — so on a case-sensitive filesystem the lookup missed and
pcall silently swallowed it. The per-host monitor overrides therefore
never loaded on either machine. Normalize the hostname to lowercase
and name the files in lowercase so any casing matches.

hypr/hyprland.lua

@@ -277,7 +277,7 @@ require("windowrule")
 
 -- Host overrides (detect machine by hostname and load matching hosts/<host>.lua)
 local hostname = (io.popen("hostname") or {}):read("*l") or ""
-hostname = hostname:gsub("%..*$", "") -- strip domain suffix
+hostname = hostname:gsub("%..*$", ""):lower() -- strip domain suffix, normalize case
 local ok, err = pcall(require, "hosts." .. hostname)
 if not ok then
     -- No host file matches this machine; use the defaults already set above.