Add Nix and environment configuration files

- Created `.envrc` for Direnv integration to manage Nix environment.
- Added `.gitignore` to exclude build artifacts and IDE files.
- Introduced `flake.nix` for Nix flake configuration and development shell setup.
- Generated `flake.lock` to lock dependencies for the Nix environment.
- Updated `go.mod` to specify Go version 1.23.
- Added `README.md` with project overview, development instructions, and troubleshooting tips.

flake.lock

@@ -0,0 +1,27 @@
+{
+  "nodes": {
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1755615617,
+        "narHash": "sha256-HMwfAJBdrr8wXAkbGhtcby1zGFvs+StOp19xNsbqdOg=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "20075955deac2583bb12f07151c2df830ef346b4",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}