fixes #18612; apply cache and memcmp for methods in arc/orc (#19749)

* try using endsWith

* use memcmp

* add cache

* cleanup

* better

* minor

* fix

* improve test coverage for methods with ARC

tests/metatype/ttypedesc3.nim

@@ -1,5 +1,6 @@
 discard """
-output: '''
+  matrix: "--mm:arc; --mm:refc"
+  output: '''
 proc Base
 proc Child
 method Base

tests/method/tgeneric_methods.nim

@@ -1,4 +1,5 @@
 discard """
+  matrix: "--mm:arc; --mm:refc"
   output: '''wow2
 X 1
 X 3'''

tests/method/tmethod_issues.nim

@@ -1,4 +1,5 @@
 discard """
+  matrix: "--mm:arc; --mm:refc"
   output: '''
 wof!
 wof!

tests/method/tmethod_various.nim

@@ -1,4 +1,5 @@
 discard """
+  matrix: "--mm:arc; --mm:refc"
   output: '''
 do nothing
 HELLO WORLD!

tests/method/tsingle_methods.nim

@@ -1,5 +1,5 @@
 discard """
-  cmd: "nim c --multimethods:off $file"
+  matrix: "--mm:arc --multimethods:off; --mm:refc --multimethods:off"
   output: '''base
 base
 base

tests/misc/parsecomb.nim

@@ -1,3 +1,7 @@
+discard """
+  matrix: "--mm:arc; --mm:refc"
+"""
+
 type Input[T] = object
   toks: seq[T]
   index: int

tests/pragmas/tlocks.nim

@@ -1,3 +1,6 @@
+discard """
+  matrix: "--mm:arc; --mm:refc"
+"""
 
 type SomeBase* = ref object of RootObj
 type SomeDerived* = ref object of SomeBase