Initial commit: Brass & Sigil monorepo

Self-hosted Minecraft modpack distribution + administration system.

- launcher/  Avalonia 12 desktop client; single-file win-x64 publish.
             Microsoft auth via XboxAuthNet, manifest+SHA-1 mod sync,
             portable install path, sidecar settings.
- server/    brass-sigil-server daemon (.NET 8, linux-x64). Wraps the
             MC subprocess, embedded Kestrel admin panel with cookie
             auth + rate limiting, RCON bridge, scheduled backups,
             BlueMap CLI integration with player markers + skin proxy,
             friend-side whitelist request flow, world wipe with seed
             selection (keep current / random / custom).
- pack/      pack.lock.json (Modrinth + manual CurseForge entries),
             data-only tweak source under tweaks/, build outputs in
             overrides/ (gitignored).
- scripts/   Build-Pack / Build-Tweaks / Update-Pack / Check-Updates
             plus Deploy-Brass.ps1 unified one-shot deploy with
             version-bump pre-flight and daemon-state detection.

launcher/manifest.example.json

@@ -0,0 +1,33 @@
+{
+  "name": "Brass & Sigil",
+  "version": "0.1.0",
+  "minecraft": {
+    "version": "1.21.1"
+  },
+  "loader": {
+    "type": "neoforge",
+    "version": "21.1.95"
+  },
+  "files": [
+    {
+      "path": "mods/create-1.21.1-6.0.10.jar",
+      "url": "https://sijbers.uk/pack/files/mods/create-1.21.1-6.0.10.jar",
+      "sha1": "0e97e49837bed766e6f28a4c95b04885d6acc353"
+    },
+    {
+      "path": "mods/create-aeronautics-bundled-1.21.1-1.2.1.jar",
+      "url": "https://sijbers.uk/pack/files/mods/create-aeronautics-bundled-1.21.1-1.2.1.jar",
+      "sha1": "fdf1ae69e8b6437e0196b3a35dd2325aa904aba9"
+    },
+    {
+      "path": "mods/distant-horizons-3.0.2-b-1.21.1.jar",
+      "url": "https://sijbers.uk/pack/files/mods/distant-horizons-3.0.2-b-1.21.1.jar",
+      "sha1": "0000000000000000000000000000000000000000"
+    },
+    {
+      "path": "config/example.cfg",
+      "url": "https://sijbers.uk/pack/files/config/example.cfg",
+      "sha1": "0000000000000000000000000000000000000000"
+    }
+  ]
+}