feat: system config updates (caddy, printing, hosts, coredump, packages)

Add Caddy reverse proxy for fc.dev, Epson printer support, extraHosts
entries, coredump limits for Antigravity, and new packages (sshpass,
nssTools, brave, audacity, calibre).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

packages.nix

@@ -80,6 +80,7 @@ in {
     yubikey-manager
     pam_u2f
     polkit_gnome # fun fact: https://gitlab.gnome.org/GNOME/gdm/-/issues/613
+    sshpass
 
     arandr
     feh
@@ -152,6 +153,7 @@ in {
     # uv
     # conda
     mkcert
+    nssTools # certutil for mkcert CA installation in browsers
     goaccess
     grafana-loki # logcli
 
@@ -168,10 +170,12 @@ in {
     libnotify # notifications
 
     # Perso
+    brave
     nextcloud-client
     rclone
+    audacity
     freeplane
-    # calibre
+    calibre
     gparted
     ticktick
     agate