Initial commit: Split Macha autonomous system into separate flake

Macha is now a standalone NixOS flake that can be imported into other
systems. This provides:

- Independent versioning
- Easier reusability
- Cleaner separation of concerns
- Better development workflow

Includes:
- Complete autonomous system code
- NixOS module with full configuration options
- Queue-based architecture with priority system
- Chunked map-reduce for large outputs
- ChromaDB knowledge base
- Tool calling system
- Multi-host SSH management
- Gotify notification integration

All capabilities from DESIGN.md are preserved.

flake.nix

@@ -0,0 +1,41 @@
+{
+  description = "Macha - AI-Powered Autonomous System Administrator";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+  };
+
+  outputs = { self, nixpkgs }: {
+    # NixOS module
+    nixosModules.default = import ./module.nix;
+    
+    # Alternative explicit name
+    nixosModules.macha-autonomous = import ./module.nix;
+
+    # For development
+    devShells = nixpkgs.lib.genAttrs [ "x86_64-linux" "aarch64-linux" ] (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        pythonEnv = pkgs.python3.withPackages (ps: with ps; [
+          requests
+          psutil
+          chromadb
+        ]);
+      in {
+        default = pkgs.mkShell {
+          packages = [ pythonEnv pkgs.git ];
+          shellHook = ''
+            echo "Macha Autonomous Development Environment"
+            echo "Python packages: requests, psutil, chromadb"
+          '';
+        };
+      }
+    );
+
+    # Formatter
+    formatter = nixpkgs.lib.genAttrs [ "x86_64-linux" "aarch64-linux" ] (system:
+      nixpkgs.legacyPackages.${system}.nixpkgs-fmt
+    );
+  };
+}
+