add exports query

queries/exports.scm

@@ -0,0 +1,25 @@
+; Names a tag binds in the scope *around* it rather than in the scope it opens.
+;
+; queries/locals.scm cannot express this: a locals query places a definition in
+; the innermost @local.scope whose span contains it, and there is no way to let
+; one out again. A tool reads this file alongside locals.scm and binds
+; @export.name in the nearest scope enclosing @export.from, not inside it.
+;
+; Only blocktranslate does this. Its asvar target is written inside the opening
+; tag — which is inside the scope, because the "with" and "count" bindings in
+; that same tag do belong to the block — but it holds the rendered text and is
+; read after the block:
+;
+;     {% blocktranslate with bar=foo asvar var %}…{% endblocktranslate %}
+;     {{ var }}
+;
+; It carries an "asvar" field rather than "variable" so locals.scm leaves it
+; alone. Every other "as name" clause is written in a tag that opens no scope,
+; so locals.scm already places those correctly and none of them belong here.
+;
+; asvar and the "with" bindings may be written in either order, so no single
+; scope span could have separated them; that is why this is a separate file
+; rather than a narrower scope in locals.scm.
+
+(blocktranslate_group
+  asvar: (identifier) @export.name) @export.from