Fix orchestration.sx parse error, add parser line/col diagnostics

The parser was reporting "Unexpected char: )" with no position info.
Added line number, column, and byte position to all parse errors.

Root cause: bind-sse-swap had one extra close paren that naive paren
counting missed because a "(" exists inside a string literal on L1074
(starts-with? trimmed "("). Parse-aware counting (skipping strings
and comments) correctly identified the imbalance.

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

shared/static/wasm/sx/orchestration.sx

@@ -1084,7 +1084,7 @@
           (with-transition use-transition
             (fn ()
               (swap-html-string target trimmed swap-style)
-              (post-swap target)))))))))
+              (post-swap target))))))))
 
 
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