feat(input): add winblend as a config option

lua/dressing/config.lua

@@ -18,6 +18,9 @@ local default_config = {
     max_width = nil,
     min_width = 20,
 
+    -- Window transparency (0-100)
+    winblend = 10,
+
     -- see :help dressing-prompt
     prompt_buffer = false,
 

lua/dressing/input.lua

@@ -182,6 +182,7 @@ setmetatable(M, {
       on_confirm = on_confirm,
       opts = opts,
     }
+    vim.api.nvim_win_set_option(winid, "winblend", config.winblend)
 
     -- Finish setting up the buffer
     vim.api.nvim_buf_set_option(bufnr, "swapfile", false)
@@ -241,6 +242,7 @@ setmetatable(M, {
         if winid == context.winid then
           context.title_winid = title_winid
         end
+        vim.api.nvim_win_set_option(title_winid, "winblend", config.winblend)
         vim.api.nvim_buf_set_lines(titlebuf, 0, -1, true, { " " .. trimmed_prompt })
         vim.api.nvim_buf_set_option(titlebuf, "bufhidden", "wipe")
       end, 5)