feat: core.async Phase 2 — dynamic var binding conveyance

Jolt's dynamic-var binding stack was a single global array, so concurrent go
blocks interleaved each other's bindings and a go block didn't see the bindings
in effect when it was spawned.

Move the binding stack into Janet's fiber-local dyn (:jolt/binding-stack): each
fiber (go block) lazily gets its own array, so bindings can't interleave. Janet
ev/go fibers inherit the parent's dyn, but go-spawn now snapshots the binding
stack at spawn time and installs a private copy in the new fiber — Clojure
binding conveyance. A go block's own (binding ...) shadows the conveyed frame.

types.janet: cur-binding-stack / snapshot-bindings / install-bindings; var-get/
var-set/push/pop use the fiber-local stack. async.janet: go-spawn conveys.

spec: core.async/binding-conveyance (4 cases — conveyance, isolation, no leak to
root, inner shadowing). jpm test green.

.beads/issues.jsonl

@@ -6,7 +6,7 @@
 {"_type":"issue","id":"jolt-alz","title":"CRITICAL: self-referential lazy-seq/lazy-cat yields only literal prefix","status":"closed","priority":1,"issue_type":"bug","owner":"yogthos@gmail.com","created_at":"2026-06-04T17:46:13Z","created_by":"Yogthos","updated_at":"2026-06-04T18:09:15Z","closed_at":"2026-06-04T18:09:15Z","dependency_count":0,"dependent_count":0,"comment_count":0}
 {"_type":"issue","id":"jolt-wec","title":"CRITICAL: multi-collection map returns unrealized thunk","status":"closed","priority":1,"issue_type":"bug","owner":"yogthos@gmail.com","created_at":"2026-06-04T17:46:12Z","created_by":"Yogthos","updated_at":"2026-06-04T18:06:02Z","closed_at":"2026-06-04T18:06:02Z","dependency_count":0,"dependent_count":0,"comment_count":0}
 {"_type":"issue","id":"jolt-5i5","title":"core.async Phase 2: dynamic var binding conveyance","description":"Snapshot/restore the global binding-stack per fiber so dynamic var bindings don't interleave across concurrent go blocks (Clojure binding conveyance).","status":"open","priority":2,"issue_type":"feature","owner":"yogthos@gmail.com","created_at":"2026-06-05T18:55:08Z","created_by":"Yogthos","updated_at":"2026-06-05T18:55:08Z","dependency_count":0,"dependent_count":0,"comment_count":0}
-{"_type":"issue","id":"jolt-tkw","title":"core.async on Janet fibers — Phase 1: API layer","description":"Implement clojure.core.async API (chan/go/\u003c!/\u003e!/\u003c!!/\u003e!!/close!/alts!/timeout/put!/take!/buffers) on top of Janet ev/ channels and fibers. go = run body in a fiber (stackful, no CPS macro needed).","status":"open","priority":2,"issue_type":"feature","owner":"yogthos@gmail.com","created_at":"2026-06-05T18:55:07Z","created_by":"Yogthos","updated_at":"2026-06-05T18:55:07Z","dependency_count":0,"dependent_count":0,"comment_count":0}
+{"_type":"issue","id":"jolt-tkw","title":"core.async on Janet fibers — Phase 1: API layer","description":"Implement clojure.core.async API (chan/go/\u003c!/\u003e!/\u003c!!/\u003e!!/close!/alts!/timeout/put!/take!/buffers) on top of Janet ev/ channels and fibers. go = run body in a fiber (stackful, no CPS macro needed).","status":"closed","priority":2,"issue_type":"feature","owner":"yogthos@gmail.com","created_at":"2026-06-05T18:55:07Z","created_by":"Yogthos","updated_at":"2026-06-05T19:17:25Z","closed_at":"2026-06-05T19:17:25Z","close_reason":"Phase 1 complete: chan/go/\u003c!/\u003e!/close!/alts!/timeout/put!/take! on Janet fibers; two-channel design (values + done) gives drain-then-nil with no leaked fibers; 16 spec cases","dependency_count":0,"dependent_count":0,"comment_count":0}
 {"_type":"issue","id":"jolt-lko","title":"clojure-test-suite: strictness — throw on malformed calls like Clojure","description":"Make jolt throw where Clojure throws (bad-shape conj!/assoc!, arithmetic on non-numbers, out-of-range indices, etc.) to satisfy the suite's ~292 p/thrown? assertions. Targeted input validation across affected fns; guard against regressing jolt's spec/conformance.","status":"closed","priority":2,"issue_type":"task","assignee":"Yogthos","owner":"yogthos@gmail.com","created_at":"2026-06-05T14:45:20Z","created_by":"Yogthos","updated_at":"2026-06-05T18:07:56Z","started_at":"2026-06-05T14:45:39Z","closed_at":"2026-06-05T18:07:56Z","close_reason":"Implemented Clojure-strict argument validation across ~30 fns; suite pass 3691-\u003e3898, p/thrown? bucket 292-\u003e~60 (remainder is platform: int 32-bit range, subs Unicode, min-key NaN, subvec floats, map-entry-as-2-vector)","dependency_count":0,"dependent_count":0,"comment_count":0}
 {"_type":"issue","id":"jolt-kxb","title":"clojure-test-suite: transducers don't short-circuit over infinite seqs (hangs)","description":"(into [] (take 5) (range)) and similar transducer-over-infinite forms hang jolt's eager evaluator (no reduced/early-termination). 7 suite files time out. Make transducing honor reduced.","status":"closed","priority":2,"issue_type":"bug","assignee":"Yogthos","owner":"yogthos@gmail.com","created_at":"2026-06-05T13:05:18Z","created_by":"Yogthos","updated_at":"2026-06-05T13:18:37Z","started_at":"2026-06-05T13:09:59Z","closed_at":"2026-06-05T13:18:37Z","close_reason":"reduce-with-reduced steps lazy seqs incrementally; transducers short-circuit over infinite seqs","dependency_count":0,"dependent_count":0,"comment_count":0}
 {"_type":"issue","id":"jolt-js6","title":"Port clojure-test-suite as integration battery","description":"Build a minimal clojure.test + portability shim so Jolt can load the external ~/src/clojure-test-suite (240 per-fn .cljc files in clojure.test format). Add a baseline-guarded integration runner following the jank-conformance pattern (skip if absent).","status":"closed","priority":2,"issue_type":"task","assignee":"Yogthos","owner":"yogthos@gmail.com","created_at":"2026-06-05T12:22:01Z","created_by":"Yogthos","updated_at":"2026-06-05T13:05:04Z","started_at":"2026-06-05T12:22:14Z","closed_at":"2026-06-05T13:05:04Z","close_reason":"Ported clojure-test-suite as baseline-guarded integration battery; surfaced+fixed 2 evaluator macro bugs","dependency_count":0,"dependent_count":0,"comment_count":0}