fix(git): escape bracket name in :G output bufnr lookup

lua/git/cmd.lua

@@ -109,13 +109,8 @@ local function run_in_split(worktree, args, conf)
         end
     end
 
-    -- Bracket naming so the buffer name doesn't pretend to be a real
-    -- file path (and doesn't collide with the `git://<revspec>` URI
-    -- form used by the BufReadCmd loader). Reused on re-run so a
-    -- second `:G show HEAD` refreshes the existing buffer in place
-    -- instead of leaving a nameless duplicate behind.
     local name = "[git " .. table.concat(args, " ") .. "]"
-    local buf = vim.fn.bufnr(name)
+    local buf = vim.fn.bufnr("\\V" .. name)
     if buf == -1 or not vim.api.nvim_buf_is_loaded(buf) then
         buf = git.new_scratch()
         pcall(vim.api.nvim_buf_set_name, buf, name)