refactor!: unify into one compose, drop airgap/mirror/dnsmasq/avahi/blessingskin

Collapse the override-file matrix into a single docker-compose.yml holding the
whole stack: drasl, minecraft, mc-backup, caddy, nmsr, uptime-kuma. Bring-up is
now just `docker compose up -d --build`.

Removed features (dead-ends for this deployment):
- airgap / full asset mirror (mirror-airgap.sh, mirror-mods.sh, 20-mirror.caddy,
  caddy local-CA export, /ca.crt)
- dnsmasq + avahi/mDNS + dns-records.sh + mdns-host-setup.sh + ENABLE_MDNS;
  DNS is now handled outside this repo (HOST_LAN_IP dropped)
- Blessing Skin auth variant (compose + 00-core-blessingskin.caddy + BS_* env)
- host-nginx-static variant (docker-compose.nginx.yml, nginx/ulicraft.conf.tmpl)
- build-stack.sh and its run modes (online/airgap/core)

Production ingress is the only path now: host nginx terminates TLS (LE certs)
in front of caddy on a localhost-only port; caddy routes every vhost by Host
header. Launcher downloads move mirror/launcher -> launcher/.

Docs: README, deploy skill, and plan/ rewritten to match; obsolete plan docs
(dnsmasq, blessing-skin, assets-mirror, full-airgap-mirror, dns-and-run-modes)
deleted.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plan/06-launcher.md

@@ -8,8 +8,8 @@ drasl account directly in the launcher (no manual JVM `-javaagent`), import the
 modpack, and play.
 
 We host the launcher installers for **all platforms** on the landing page
-(`ulicraft.local`), served by Caddy from `./mirror/launcher/`. A script downloads
-the latest release assets ahead of time so the party is fully offline.
+(`ulicraft.net`), served by Caddy from `./launcher/` (mounted at `/srv/launcher`,
+reachable at `/launcher/`). A script downloads the release assets ahead of time.
 
 ## Release assets (latest = 11.0.2.0)
 
@@ -26,12 +26,12 @@ Setup `.exe`, macOS `.dmg`, Linux `.AppImage`.
 
 ```bash
 #!/usr/bin/env bash
-# Download all FjordLauncherUnlocked release assets for offline hosting.
+# Download all FjordLauncherUnlocked release assets for local hosting.
 # Halts on any error or ambiguity (no silent partial downloads).
 set -euo pipefail
 
 REPO="hero-persson/FjordLauncherUnlocked"
-DEST_ROOT="$(dirname "$0")/../mirror/launcher"
+DEST_ROOT="$(dirname "$0")/../launcher"
 API="https://api.github.com/repos/${REPO}/releases/latest"
 
 command -v curl >/dev/null || { echo "curl required"; exit 1; }
@@ -59,13 +59,13 @@ ln -sfn "$tag" "${DEST_ROOT}/latest"
 echo "Done. ${#urls[@]} assets in ${dest}"
 ```
 
-Caddy mount: `./mirror/launcher:/srv/www/launcher:ro`.
+Caddy mount: `./launcher:/srv/launcher:ro` (served at `/launcher/…`).
 
 ### Stable symlinks (so landing links survive version bumps)
 
 The landing page (`09-landing.md`) links to **fixed** filenames, not versioned
 ones. After downloading, `fetch-launcher.sh` must create these symlinks under
-`mirror/launcher/latest/` pointing at the real assets:
+`launcher/latest/` pointing at the real assets:
 
 - `fjord-windows-setup.exe`     → Windows Setup `.exe` (x64)
 - `fjord-macos.dmg`             → macOS `.dmg`
@@ -78,22 +78,19 @@ sync with `landing/src/data/site.ts`.**
 
 ## Per-guest flow
 
-1. Open `http://ulicraft.local`, download launcher for their OS, install.
+1. Open `https://ulicraft.net`, download launcher for their OS, install.
 2. Add account: authlib-injector type, URL
-   `http://auth.ulicraft.local/authlib-injector`, drasl username/password.
-3. (Offline) Settings → APIs → **Assets Server** =
-   `https://assets.ulicraft.local/` so the heavy asset download comes from the LAN
-   mirror (see 10-assets-mirror.md). Requires trusting the local CA.
-4. Import the modpack (packwiz URL `http://packwiz.ulicraft.local/pack.toml`,
+   `https://auth.ulicraft.net/authlib-injector`, drasl username/password.
+3. Import the modpack (packwiz URL `https://pack.ulicraft.net/pack.toml`,
    or a shared instance zip).
-5. Connect to `mc.ulicraft.local:25565`.
+4. Connect to `mc.ulicraft.net:25565`.
 
 ## Tasks
 
 - [ ] Create `tooling/fetch-launcher.sh` (above); `chmod +x`
-- [ ] Extend script: create stable symlinks (win/mac/linux) in `mirror/launcher/latest/`
-- [ ] Run it pre-party while online; verify all assets land in `./mirror/launcher/<tag>/`
-- [ ] `.gitignore` `./mirror/` (done)
+- [ ] Extend script: create stable symlinks (win/mac/linux) in `launcher/latest/`
+- [ ] Run it pre-party; verify all assets land in `./launcher/<tag>/`
+- [ ] `.gitignore` `./launcher/` (done)
 - [ ] Landing page DONE — `landing/` Astro project, builds to `www/` (see 09-landing.md)
 - [ ] Confirm Fjord authlib-injector account flow against drasl
 - [ ] Decide whether to ship a pre-built instance zip vs packwiz URL import