feat(lua): deprecate vim.tbl_add_reverse_lookup

runtime/lua/vim/shared.lua

@@ -465,9 +465,12 @@ end
 --- `tbl_add_reverse_lookup { A = 1 } == { [1] = 'A', A = 1 }`
 ---
 --- Note that this *modifies* the input.
+---@deprecated
 ---@param o table Table to add the reverse to
 ---@return table o
 function vim.tbl_add_reverse_lookup(o)
+  vim.deprecate('vim.tbl_add_reverse_lookup', nil, '0.12')
+
   --- @cast o table<any,any>
   --- @type any[]
   local keys = vim.tbl_keys(o)