HS: generator hand-rolls + transition possessive target (+4 tests)

Parser: add 'the ...' as a recognized transition target in parse-transition-cmd's
tgt cond, enabling 'transition the next <div/>'s *width from A to B'.

Generator MANUAL_TEST_BODIES for 4 previously-SKIP tests:
- can transition on query ref with possessive (transition suite, 17/17)
- can write to next element with put command (relativePositionalExpression, 23/23)
- parse error at EOF on trailing newline does not crash (core/parser, 13/14)
- halt works outside of event context (halt suite, 7/7)

Also fix hs-kernel-eval.js navigator assignment for Node.js v22 (read-only global).

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

tests/hs-kernel-eval.js

@@ -127,7 +127,7 @@ globalThis.document = {
 globalThis.CustomEvent = Ev;
 globalThis.Event = Ev;
 globalThis.window = globalThis;
-globalThis.navigator = { userAgent: 'node' };
+try { globalThis.navigator = { userAgent: 'node' }; } catch(e) { Object.defineProperty(globalThis, 'navigator', { value: { userAgent: 'node' }, writable: true, configurable: true }); }
 globalThis.location = { href:'http://localhost/', pathname:'/', search:'', hash:'' };
 globalThis.history = { pushState(){}, replaceState(){} };
 globalThis.getSelection = () => ({ toString: () => '' });