Expose py-editor code content read/write (#2087)

* Expose py-editor code content read/write

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

pyscript.core/src/plugins/py-editor.js

@@ -184,6 +184,21 @@ const init = async (script, type, interpreter) => {
     let target;
     defineProperties(script, {
         target: { get: () => target },
+        code: {
+            get: () => context.pySrc,
+            set: (insert) => {
+                if (isSetup) return;
+                editor.update([
+                    editor.state.update({
+                        changes: {
+                            from: 0,
+                            to: editor.state.doc.length,
+                            insert,
+                        },
+                    }),
+                ]);
+            },
+        },
         process: {
             /**
              * Simulate a setup node overriding the source to evaluate.