HS: on EVENT from SRC or EVENT from SRC multi-source listener (+1 test)

Parser: limit `from SOURCE` to parse-collection/cmp/arith/poss/atom
  (stops before parse-logical so `or` is not consumed as binary op),
  then collect `or EVENT from SOURCE` pairs via recursive collect-ors!.
  Adds :or-sources key to the on-feature parts list.

Compiler: scan-on gains or-sources param (11th); new :or-sources cond
  clause extracts the list; terminal `true` branch wraps on-call in
  (do on-call (hs-on target event handler) ...) for each extra source.

Test: "can handle an or after a from clause" moved from skip-list to
  MANUAL_TEST_BODIES and now passes (1478/1496).

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

tests/playwright/generate-sx-tests.py

@@ -111,7 +111,6 @@ SKIP_TEST_NAMES = {
     "each behavior installation has its own event queue",
     "can catch exceptions thrown in hyperscript functions",
     "can catch exceptions thrown in js functions",
-    "can handle an or after a from clause",
     # upstream 'fetch' category — real DocumentFragment semantics (`its childElementCount`
     # after `as html`) not exercisable with our DOM mock.
     "can do a simple fetch w/ html",
@@ -155,6 +154,22 @@ MANUAL_TEST_BODIES = {
         '      (assert-contains "foo" _names)',
         '      (assert-contains "bar" _values))',
     ],
+    "can handle an or after a from clause": [
+        '    (hs-cleanup!)',
+        '    (let ((_d1 (dom-create-element "div"))',
+        '          (_d2 (dom-create-element "div"))',
+        '          (_el (dom-create-element "div")))',
+        '      (dom-set-attr _d1 "id" "d1")',
+        '      (dom-set-attr _d2 "id" "d2")',
+        '      (dom-set-attr _el "_" "on click from #d1 or click from #d2 increment @count then put @count into me")',
+        '      (dom-append (dom-body) _d1)',
+        '      (dom-append (dom-body) _d2)',
+        '      (dom-append (dom-body) _el)',
+        '      (hs-activate! _el)',
+        '      (dom-dispatch _d1 "click" nil)',
+        '      (dom-dispatch _d2 "click" nil)',
+        '      (assert= (dom-text-content _el) "2"))',
+    ],
     "raises a helpful error when the worker plugin is not installed": [
         '    (hs-cleanup!)',
         '    (let ((caught nil))',