sx-tools: WASM kernel updates, TW/CSSX rework, content refresh, new debugging tools

Build tooling: updated OCaml bootstrapper, compile-modules, bundle.sh, sx-build-all.
WASM browser: rebuilt sx_browser.bc.js/wasm, sx-platform-2.js, .sxbc bytecode files.
CSSX/Tailwind: reworked cssx.sx templates and tw-layout, added tw-type support.
Content: refreshed essays, plans, geography, reactive islands, docs, demos, handlers.
New tools: bisect_sxbc.sh, test-spa.js, render-trace.sx, morph playwright spec.
Tests: added test-match.sx, test-examples.sx, updated test-tw.sx and web tests.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

shared/sx/templates/tw-layout.sx

@@ -36,11 +36,8 @@
           (= (len rest) 2)
           (or (= (first rest) "x") (= (first rest) "y")))
         (let
-          ((v (tw-spacing-value (nth rest 1))) (dir (first rest)))
-          (if
-            (nil? v)
-            nil
-            (if (= dir "x") (str "column-gap:" v) (str "row-gap:" v))))
+          ((v (tw-spacing-value (last rest))) (dir (first rest)))
+          (if (nil? v) nil (if (= dir "x") {:suffix ">*+*" :css (str "margin-left:" v)} {:suffix ">*+*" :css (str "margin-top:" v)})))
         (and (= head "flex") (empty? rest))
         "display:flex"
         (and (= head "flex") (= (len rest) 1))