Refactor(English): Rename all files and identifiers from Dutch to English

Renamed files: constanten→constants, adt-positie→adt-position,
adt-doolhof→adt-maze, adt-sleutel→adt-key, adt-tijdslimiet→adt-timer,
adt-teken→adt-draw, adt-spel→adt-game. All message names, variables,
comments, and tests converted to English.

Also fixed counter location bug (time-label x/y were swapped).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

pacman-project/tests/test-position.rkt

@@ -0,0 +1,57 @@
+#lang r7rs
+
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;;                           Tests: Position ADT                             ;;
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(define-library (pacman-project tests test-position)
+  (import (scheme base)
+          (pp1 tests)
+          (pacman-project adt-position))
+  (export test)
+
+  (begin
+
+    ;; Test creation and getters
+    (define (test-creation)
+      (define pos (make-position 5 10))
+      (check-eq? (pos 'row) 5 "Row should be 5")
+      (check-eq? (pos 'col) 10 "Col should be 10"))
+
+    ;; Test mutators
+    (define (test-mutators)
+      (define pos (make-position 0 0))
+      ((pos 'row!) 3)
+      ((pos 'col!) 7)
+      (check-eq? (pos 'row) 3 "Row should be 3 after row!")
+      (check-eq? (pos 'col) 7 "Col should be 7 after col!"))
+
+    ;; Test equal?
+    (define (test-equal)
+      (define p1 (make-position 5 10))
+      (define p2 (make-position 5 10))
+      (define p3 (make-position 5 11))
+      (check ((p1 'equal?) p2) "Equal positions should match")
+      (check (not ((p1 'equal?) p3)) "Different positions should not match"))
+
+    ;; Test move
+    (define (test-move)
+      (define pos (make-position 5 10))
+      (define new-pos ((pos 'move) -1 0))
+      (check-eq? (new-pos 'row) 4 "Row should be 4 after move up")
+      (check-eq? (new-pos 'col) 10 "Col unchanged after move up")
+      ;; Original position must not change
+      (check-eq? (pos 'row) 5 "Original row must not change"))
+
+    ;; Test that two objects are not eq?
+    (define (test-identity)
+      (define p1 (make-position 1 1))
+      (define p2 (make-position 1 1))
+      (check (not (eq? p1 p2)) "Two position objects must not be eq?"))
+
+    (define (test)
+      (run-test test-creation "Position: creation and getters")
+      (run-test test-mutators "Position: mutators")
+      (run-test test-equal "Position: equal?")
+      (run-test test-move "Position: move")
+      (run-test test-identity "Position: identity"))))