HS: tokenizer-stream API → 13 tests pass (-13 skips)

lib/hyperscript/tokenizer.sx — added cursor + follow-set wrapper over
the existing flat-list tokenize output:

  hs-stream src                 → {:tokens :pos :follows :last-match :last-ws}
  hs-stream-current  s          → next non-WS token (skips WS, captures :last-ws)
  hs-stream-match    s value    → consume if value matches & not in follow set
  hs-stream-match-type s ...types → consume if upstream type name matches
  hs-stream-match-any  s ...names → consume if value matches any name
  hs-stream-match-any-op s ...ops → consume if op token & value matches
  hs-stream-peek     s value n  → look n non-WS tokens ahead, no consume
  hs-stream-consume-until s marker     → collect tokens until marker
  hs-stream-consume-until-ws  s        → collect until next whitespace
  hs-stream-push-follow! / pop-follow!
  hs-stream-push-follows! / pop-follows! n
  hs-stream-clear-follows! → saved   /  restore-follows! saved
  hs-stream-last-match / last-ws

hs-stream-type-map maps our lowercase type names to upstream's
("ident" → "IDENTIFIER", "number" → "NUMBER", etc.) so type-based
matching works against upstream test expectations.

13 tokenizer-stream tests now pass; 30/30 in hs-upstream-core/tokenizer.

Skips remaining: 5 (down from 18).
  - 2 template-component scope tests
  - 1 async event dispatch (until event keyword works)
  - left for later: needs more architectural work

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

tests/hs-run-filtered.js

@@ -967,25 +967,6 @@ for(let i=startTest;i<Math.min(endTest,testCount);i++){
     // 'repeat until event' loop suspends the OCaml kernel waiting for an
     // event that is never fired from outside the K.eval call chain.
     "until event keyword works",
-    // === Tokenizer-stream API tests (13) — upstream exposes a streaming token
-    // API on _hyperscript.internals.tokenizer (matchToken, peekToken, consumeUntil,
-    // pushFollow, etc.). Our lib/hyperscript/tokenizer.sx returns a flat token list
-    // and the parser keeps stream state internally as closures. Making these tests
-    // pass would require exposing a token-stream wrapper as a primitive. The
-    // tokenizer is correct; it just doesn't expose this API surface. ===
-    "matchToken consumes and returns on match",
-    "matchToken honors the follow set",
-    "matchTokenType matches by type",
-    "matchOpToken matches operators by value",
-    "matchAnyToken and matchAnyOpToken try each option",
-    "peekToken skips whitespace when looking ahead",
-    "consumeUntil collects tokens up to a marker",
-    "consumeUntilWhitespace stops at first whitespace",
-    "pushFollow/popFollow nest follow-set boundaries",
-    "pushFollows/popFollows push and pop in bulk",
-    "clearFollows/restoreFollows round-trip the follow set",
-    "lastMatch returns the last consumed token",
-    "lastWhitespace reflects whitespace before the current token",
     // === Template-component scope tests (2) — upstream uses
     //     <script type="text/hyperscript-template" component="...">
     // for HTML-template-based custom-element components. Our defcomp uses SX