refactor(vim.iter)!: remove vim.iter.map/filter/totable #26138

Problem:
The use-case for the convenience functions vim.iter.map(),
vim.iter.filter(), vim.iter.totable() is not clear.

Solution:
Drop them for now. We can revisit after 0.10 release.

runtime/lua/vim/iter.lua

@@ -60,9 +60,6 @@
 --- vim.iter(rb):totable()
 --- -- { "a", "b" }
 --- ```
----
---- In addition to the |vim.iter()| function, the |vim.iter| module provides
---- convenience functions like |vim.iter.filter()| and |vim.iter.totable()|.
 
 --- LuaLS is bad at generics which this module mostly deals with
 --- @diagnostic disable:no-unknown
@@ -1092,55 +1089,6 @@ function ListIter.new(t)
   return it
 end
 
---- Collects an |iterable| into a table.
----
---- ```lua
---- -- Equivalent to:
---- vim.iter(f):totable()
---- ```
----
----@param f function Iterator function
----@return table
-function M.totable(f, ...)
-  return Iter.new(f, ...):totable()
-end
-
---- Filters a table or other |iterable|.
----
---- ```lua
---- -- Equivalent to:
---- vim.iter(src):filter(f):totable()
---- ```
----
----@see |Iter:filter()|
----
----@param f fun(...):boolean Filter function. Accepts the current iterator or table values as
----                       arguments and returns true if those values should be kept in the
----                       final table
----@param src table|function Table or iterator function to filter
----@return table
-function M.filter(f, src, ...)
-  return Iter.new(src, ...):filter(f):totable()
-end
-
---- Maps a table or other |iterable|.
----
---- ```lua
---- -- Equivalent to:
---- vim.iter(src):map(f):totable()
---- ```
----
----@see |Iter:map()|
----
----@param f fun(...): any? Map function. Accepts the current iterator or table values as
----                        arguments and returns one or more new values. Nil values are removed
----                        from the final table.
----@param src table|function Table or iterator function to filter
----@return table
-function M.map(f, src, ...)
-  return Iter.new(src, ...):map(f):totable()
-end
-
 return setmetatable(M, {
   __call = function(_, ...)
     return Iter.new(...)