HS E37: tokenizer-as-API 17/17 (+fixes)

- runtime.sx: fix extra ) in hs-tokens-of (parse error); add hs-eof-sentinel,
  hs-raw->api-token, hs-normalize-raw-tokens, hs-tokens-of, stream helpers,
  hs-token-type/value/op?; add \$ escape to hs-template
- tokenizer.sx: fix read-number double-dot bug (1.1.1 → 3 tokens); fix t-emit!
  eof call (3→2 args); add bare $ case to scan-template!
- compiler.sx: add \$ escape to tpl-collect template interpolation
- generate-sx-tests.py: preserve \$ in process_hs_val; add generate_tokenizer_test
- regen spec/tests/test-hyperscript-behavioral.sx: 17 tokenizer tests generated
- plans/hs-conformance-to-100.md: row 37 marked done +17

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

plans/hs-conformance-to-100.md

@@ -131,7 +131,7 @@ All five have design docs on their own worktree branches pending review + merge.
 
 36. **[design-done, pending review — `plans/designs/e36-websocket.md` on `worktree-agent-a9daf73703f520257`] WebSocket + `socket`** — 16 tests. Upstream shape is `socket NAME URL [with timeout N] [on message [as JSON] …] end` with an **implicit `.rpc` Proxy** (ES6 Proxy lives in JS, not SX), not `with proxy { send, receive }` as this row previously claimed. Design doc has 8-commit checklist, +12–16 delta estimate. Ship only with intentional design review.
 
-37. **[design-done, pending review — `plans/designs/e37-tokenizer-api.md` on `worktree-agent-a6bb61d59cc0be8b4`] Tokenizer-as-API** — 17 tests. Expose tokens as inspectable SX data via `hs-tokens-of` / `hs-stream-token` / `hs-token-type` etc; type-map current `hs-tokenize` output to upstream SCREAMING_SNAKE_CASE. 8-step checklist, +16–17 delta.
+37. **[done +17]** Tokenizer-as-API — `hs-tokens-of` / `hs-stream-token` / `hs-token-type` / `hs-token-value` / `hs-token-op?`; type-map + normalize; `read-number` dot-stop fix; `\$` template escape in compiler + runtime; generator pattern in `generate-sx-tests.py`. 17/17.
 
 38. **[design-done, pending review — `plans/designs/e38-sourceinfo.md` on `agent-e38-sourceinfo`] SourceInfo API** — 4 tests. Inline span-wrapper strategy (not side-channel dict) with compiler-entry unwrap. 4-commit plan.