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Neovim version (nvim -v)

0.11.4

Operating system/version

macOS 26

Describe the bug

When trying to send a visual selection (not a visual line selection) to the AI CLI agent, if the initial column and the final column are the same, the send selection is wrong (missing the end of the selection).

Steps To Reproduce

1. open AI CLI agent.
2. select some text with visual selection ensuring that the initial and final column are the same.
3. send the selection to the AI CLI agent.

Expected Behavior

In the screencast, I'm expecting that first selection to be

@README.md :L4:C13-L11:C13

but I'm getting

@README.md :L4:C13

(the second selection in the screencast is just used to show that if initial column and final column are different, the send cmd behaves as expected)

Repro

vim.g.mapleader = " "

vim.env.LAZY_STDPATH = ".repro"
load(vim.fn.system("curl -s https://raw.githubusercontent.com/folke/lazy.nvim/main/bootstrap.lua"))()

require("lazy.minit").repro({
  spec = {
    {
      "folke/sidekick.nvim",
      opts = {},
      keys = {
        {
          "<leader>aa",
          function()
            require("sidekick.cli").toggle()
          end,
          desc = "Sidekick Toggle CLI",
        },
        {
          "<leader>at",
          function()
            require("sidekick.cli").send({ msg = "{this}" })
          end,
          mode = { "x", "n" },
          desc = "Send This",
        },
      },
    },
  },
})