docs(builtin): fix some missing lines (#24759)

Some things got chopped off in the PR that removed method syntax examples.
These were all that I found.

src/nvim/eval.lua

@@ -796,6 +796,8 @@ M.funcs = {
       with a listed buffer, that one is returned.  Next unlisted
       buffers are searched for.
       If the {buf} is a String, but you want to use it as a buffer
+      number, force it to be a Number by adding zero to it: >vim
+      	echo bufname("3" + 0)
       <If the buffer doesn't exist, or doesn't have a name, an empty
       string is returned. >vim
       	echo bufname("#")	" alternate buffer name
@@ -5413,6 +5415,9 @@ M.funcs = {
     base = 1,
     desc = [=[
       Bitwise invert.  The argument is converted to a number.  A
+      List, Dict or Float argument causes an error.  Example: >vim
+      	let bits = invert(bits)
+      <
     ]=],
     name = 'invert',
     params = { { 'expr', 'any' } },
@@ -8150,6 +8155,9 @@ M.funcs = {
       {object} can be a |List| or a |Blob|.
       Returns {object}.
       Returns zero if {object} is not a List or a Blob.
+      If you want an object to remain unmodified make a copy first: >vim
+      	let revlist = reverse(copy(mylist))
+      <
     ]=],
     name = 'reverse',
     params = { { 'object', 'any' } },