hs: query targets, prolog hook, loop scripts, new plans, WASM regen

Hyperscript compiler/runtime:
- query target support in set/fire/put commands
- hs-set-prolog-hook! / hs-prolog-hook / hs-prolog in runtime
- runtime log-capture cleanup

Scripts: sx-loops-up/down, sx-hs-e-up/down, sx-primitives-down
Plans: datalog, elixir, elm, go, koka, minikanren, ocaml, hs-bucket-f,
       designs (breakpoint, null-safety, step-limit, tell, cookies, eval,
       plugin-system)
lib/prolog/hs-bridge.sx: initial hook-based bridge draft
lib/common-lisp/tests/runtime.sx: CL runtime tests

WASM: regenerate sx_browser.bc.js from updated hs sources

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

shared/static/scripts/sx-browser.js

@@ -41,7 +41,7 @@
   // =========================================================================
 
   var NIL = Object.freeze({ _nil: true, toString: function() { return "nil"; } });
-  var SX_VERSION = "2026-05-01T18:54:28Z";
+  var SX_VERSION = "2026-05-01T19:10:01Z";
 
   function isNil(x) { return x === NIL || x === null || x === undefined; }
   function isSxTruthy(x) { return x !== false && !isNil(x); }
@@ -186,6 +186,7 @@
     if (x._hash_table) return "hash-table";
     if (x._sxset) return "set";
     if (x._regexp) return "regexp";
+    if (x._bytevector) return "bytevector";
     if (x._rational) return "rational";
     if (typeof Node !== "undefined" && x instanceof Node) return "dom-node";
     if (Array.isArray(x)) return "list";
@@ -1213,6 +1214,73 @@
   };
 
 
+  // stdlib.bytevectors — R7RS bytevector type backed by Uint8Array
+  function SxBytevector(size_or_buf) {
+    if (size_or_buf instanceof Uint8Array) {
+      this.data = size_or_buf;
+    } else {
+      this.data = new Uint8Array(typeof size_or_buf === "number" ? size_or_buf : 0);
+    }
+    this._bytevector = true;
+  }
+  SxBytevector.prototype._type = "bytevector";
+  PRIMITIVES["make-bytevector"] = function(n, fill) {
+    var bv = new SxBytevector(n);
+    if (fill !== undefined) bv.data.fill(fill & 0xff);
+    return bv;
+  };
+  PRIMITIVES["bytevector?"] = function(v) { return v instanceof SxBytevector; };
+  PRIMITIVES["bytevector-length"] = function(bv) { return bv.data.length; };
+  PRIMITIVES["bytevector-u8-ref"] = function(bv, i) { return bv.data[i]; };
+  PRIMITIVES["bytevector-u8-set!"] = function(bv, i, byte) { bv.data[i] = byte & 0xff; return NIL; };
+  PRIMITIVES["bytevector-copy"] = function(bv, start, end_) {
+    var s = start === undefined ? 0 : start;
+    var e = end_ === undefined ? bv.data.length : end_;
+    return new SxBytevector(bv.data.slice(s, e));
+  };
+  PRIMITIVES["bytevector-copy!"] = function(dst, at, src, start, end_) {
+    var s = start === undefined ? 0 : start;
+    var e = end_ === undefined ? src.data.length : end_;
+    dst.data.set(src.data.subarray(s, e), at);
+    return NIL;
+  };
+  PRIMITIVES["bytevector-append"] = function() {
+    var total = 0;
+    for (var i = 0; i < arguments.length; i++) total += arguments[i].data.length;
+    var result = new Uint8Array(total);
+    var pos = 0;
+    for (var i = 0; i < arguments.length; i++) {
+      result.set(arguments[i].data, pos);
+      pos += arguments[i].data.length;
+    }
+    return new SxBytevector(result);
+  };
+  PRIMITIVES["utf8->string"] = function(bv, start, end_) {
+    var s = start === undefined ? 0 : start;
+    var e = end_ === undefined ? bv.data.length : end_;
+    var dec = new TextDecoder("utf-8");
+    return dec.decode(bv.data.subarray(s, e));
+  };
+  PRIMITIVES["string->utf8"] = function(str, start, end_) {
+    var enc = new TextEncoder();
+    var full = enc.encode(str);
+    var s = start === undefined ? 0 : start;
+    var e = end_ === undefined ? full.length : end_;
+    return new SxBytevector(full.slice(s, e));
+  };
+  PRIMITIVES["bytevector->list"] = function(bv) {
+    var out = [];
+    for (var i = 0; i < bv.data.length; i++) out.push(bv.data[i]);
+    return out;
+  };
+  PRIMITIVES["list->bytevector"] = function(lst) {
+    if (!Array.isArray(lst)) lst = [];
+    var b = new Uint8Array(lst.length);
+    for (var i = 0; i < lst.length; i++) b[i] = lst[i] & 0xff;
+    return new SxBytevector(b);
+  };
+
+
   function isPrimitive(name) { return name in PRIMITIVES; }
   function getPrimitive(name) { return PRIMITIVES[name]; }