refact: move escape and remove alias

lua/telekasten/utils/init.lua

@@ -1,5 +1,16 @@
 local M = {}
 
+--- Escapes Lua pattern characters for use in gsub
+function M.escape(s)
+    -- return s:gsub("[^%w]", "%%%1") -- Escape everything ?
+    return s:gsub("[%%%]%^%-$().[*+?]", "%%%1")
+end
+
+--- Returns string with listed chars removed (= safer gsub)
+function M.strip(s, chars_to_remove)
+    return s:gsub("[" .. M.escape(chars_to_remove) .. "]", "")
+end
+
 -- strip an extension from a file name, escaping "." properly, eg:
 -- strip_extension("path/Filename.md", ".md") -> "path/Filename"
 local function strip_extension(str, ext)