docs(v3.5.0): update README for integrated mg_dotfiles and security improvements

- Integrated mg_dotfiles as regular directory (not submodule)
- Added .zshrc.local.example template for local configs without secrets
- Added mg_dotfiles/zsh/.zshrc.local to .gitignore to protect API keys
- Updated README to reflect mg_dotfiles integration and new structure
- Added nvim configuration directory with LazyVim setup

mg_dotfiles/nvim/lua/plugins/blink.lua

@@ -0,0 +1,36 @@
+return {
+  "saghen/blink.cmp",
+  lazy = true,
+  dependencies = { "saghen/blink.compat" },
+  opts = {
+    sources = {
+      default = { "avante_commands", "avante_mentions", "avante_files" },
+      compat = {
+        "avante_commands",
+        "avante_mentions",
+        "avante_files",
+      },
+      -- LSP score_offset is typically 60
+      providers = {
+        avante_commands = {
+          name = "avante_commands",
+          module = "blink.compat.source",
+          score_offset = 90,
+          opts = {},
+        },
+        avante_files = {
+          name = "avante_files",
+          module = "blink.compat.source",
+          score_offset = 100,
+          opts = {},
+        },
+        avante_mentions = {
+          name = "avante_mentions",
+          module = "blink.compat.source",
+          score_offset = 1000,
+          opts = {},
+        },
+      },
+    },
+  },
+}