feat(ai): add avante.nvim for a better AI experience (#4440)

I switched over to https://github.com/yetone/avante.nvim and I think
this is the best experience in terms of UI and easiness to add patches
to your code.

I'm recommending it to everyone.

~~However, I couldn't make render-markdown to work on Avante. It seems
that my spec here is running before the one defined in
extras/lang/markdown.lua and getting overwritten even though I added
`optional = true`. I'll try to dig in deeper, but if someone has any
pointers, I'd appreciate it.~~

  - Fixes #4394

---------

Co-authored-by: PatMulligan <43773168+PatMulligan@users.noreply.github.com>
Co-authored-by: Iordanis Petkakis <12776461+dpetka2001@users.noreply.github.com>
Co-authored-by: Folke Lemaitre <folke.lemaitre@gmail.com>
Co-authored-by: Claude <noreply@anthropic.com>

lua/lazyvim/plugins/extras/ai/avante.lua

@@ -0,0 +1,86 @@
+return {
+  { "MunifTanjim/nui.nvim", lazy = true },
+
+  {
+    "yetone/avante.nvim",
+    build = vim.fn.has("win32") ~= 0 and "powershell -ExecutionPolicy Bypass -File Build.ps1 -BuildFromSource false"
+      or "make",
+    event = "VeryLazy",
+    opts = {
+      provider = "copilot",
+      selection = {
+        hint_display = "none",
+      },
+    },
+    cmd = {
+      "AvanteAsk",
+      "AvanteBuild",
+      "AvanteChat",
+      "AvanteClear",
+      "AvanteEdit",
+      "AvanteFocus",
+      "AvanteHistory",
+      "AvanteModels",
+      "AvanteRefresh",
+      "AvanteShowRepoMap",
+      "AvanteStop",
+      "AvanteSwitchProvider",
+      "AvanteToggle",
+    },
+    keys = {
+      { "n", "<leader>aa", "<cmd>AvanteAsk<CR>", desc = "Ask Avante" },
+      { "n", "<leader>ac", "<cmd>AvanteChat<CR>", desc = "Chat with Avante" },
+      { "n", "<leader>ae", "<cmd>AvanteEdit<CR>", desc = "Edit Avante" },
+      { "n", "<leader>af", "<cmd>AvanteFocus<CR>", desc = "Focus Avante" },
+      { "n", "<leader>ah", "<cmd>AvanteHistory<CR>", desc = "Avante History" },
+      { "n", "<leader>am", "<cmd>AvanteModels<CR>", desc = "Select Avante Model" },
+      { "n", "<leader>an", "<cmd>AvanteChatNew<CR>", desc = "New Avante Chat" },
+      { "n", "<leader>ap", "<cmd>AvanteSwitchProvider<CR>", desc = "Switch Avante Provider" },
+      { "n", "<leader>ar", "<cmd>AvanteRefresh<CR>", desc = "Refresh Avante" },
+      { "n", "<leader>as", "<cmd>AvanteStop<CR>", desc = "Stop Avante" },
+      { "n", "<leader>at", "<cmd>AvanteToggle<CR>", desc = "Toggle Avante" },
+    },
+  },
+
+  -- support for image pasting
+  {
+    "HakonHarnes/img-clip.nvim",
+    event = "VeryLazy",
+    optional = true,
+    opts = {
+      -- recommended settings
+      default = {
+        embed_image_as_base64 = false,
+        prompt_for_file_name = false,
+        drag_and_drop = {
+          insert_mode = true,
+        },
+        -- required for Windows users
+        use_absolute_path = true,
+      },
+    },
+  },
+
+  -- Make sure to set this up properly if you have lazy=true
+  {
+    "MeanderingProgrammer/render-markdown.nvim",
+    optional = true,
+    opts = {
+      file_types = { "markdown", "Avante" },
+    },
+    ft = { "markdown", "Avante" },
+  },
+
+  -- blink.cmp source for avante.nvim
+  {
+    "saghen/blink.cmp",
+    optional = true,
+    specs = { "Kaiser-Yang/blink-cmp-avante" },
+    opts = {
+      sources = {
+        default = { "avante" },
+        providers = { avante = { module = "blink-cmp-avante", name = "Avante" } },
+      },
+    },
+  },
+}