fix(core): make `metadata` available in production (#3714)

Co-authored-by: Jovi De Croock <[e-mail]>

.changeset/fluffy-starfishes-unite.md

···
+---
+'@urql/core': minor
+---
+
+Remove `addMetadata` transform where we'd strip out metadata for production environments, this particularly affects `OperationResult.context.metadata.cacheOutcome`

scripts/babel/transform-debug-target.mjs

···
   process.env.NODE_ENV !== 'production' ? NODE : undefined
 `.trim();
 
-const noopTransformTemplate = `
-  process.env.NODE_ENV !== 'production' ? NODE : FALLBACK
-`.trim();
-
 const plugin = ({ template, types: t }) => {
   const wrapWithDevCheck = template.expression(warningDevCheckTemplate, {
     placeholderPattern: /^NODE$/,
-  });
-
-  const wrapWithNoopTransform = template.expression(noopTransformTemplate, {
-    placeholderPattern: /^(NODE|FALLBACK)$/,
   });
 
   let name = 'unknownExchange';
···
           }
 
           path.replaceWith(wrapWithDevCheck({ NODE: path.node }));
-        } else if (path.node.callee.name === 'addMetadata') {
-          path.node[visited] = true;
-          path.replaceWith(
-            wrapWithNoopTransform({
-              NODE: path.node,
-              FALLBACK: path.node.arguments[0],
-            })
-          );
         }
       },
     },