apl: migrate conformance onto shared lib/guest driver (counters mode)

Replaces the bespoke 116-line conformance.sh with a conformance.conf + 1-line
exec shim, reusing lib/guest/conformance.sh. Surfaced + fixed a silent undercount:
the old awk extractor reported pipeline=40, but pipeline.sx has 152 assertions —
real total is 562/562, not 450/450. Driver reads counter globals directly.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/apl/test-harness.sx

@@ -0,0 +1,15 @@
+; lib/apl/test-harness.sx — counters + assertion fn for the shared conformance
+; driver (lib/guest/conformance.sh, MODE=counters). Loaded as a PRELOAD so each
+; suite starts from a fresh 0/0; suites call (apl-test name got expected).
+
+(define apl-test-pass 0)
+(define apl-test-fail 0)
+
+(define
+  apl-test
+  (fn
+    (name got expected)
+    (if
+      (= got expected)
+      (set! apl-test-pass (+ apl-test-pass 1))
+      (set! apl-test-fail (+ apl-test-fail 1)))))