fix: keep SDL fetch routing after a plugin remount

dispose() removed the fetch route but kept the cached SDL runtime, and
the route was only installed on first load, so a re-initialised plugin
could reuse the runtime and download packages through a replaced fetch.

- install the route at the start of every run (no-op while active)
- dispose() drops the cached runtime so it is freed, not reused
- main.js clears its cached sdl.js promise and removes the script tag on
  destroy, so a later init loads a fresh module

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Author: bajrangCoder

plugin.zip

@@ -33,6 +33,7 @@ class Python {
 	/** number of code runs still waiting for the worker */
 	#running = 0;
 	#sdlPromise = null;
+	$sdlScript = null;
 	/** bumped by every run and when the console closes, to drop stale runs */
 	#runId = 0;
 	#sdlAllowed = false;
@@ -244,6 +245,7 @@ class Python {
 	#loadSdl() {
 		this.#sdlPromise ??= new Promise((resolve, reject) => {
 			const $script = tag("script", { src: `${this.baseUrl}sdl.js` });
+			this.$sdlScript = $script;
 			$script.onload = () => {
 				if (window.acodePythonSdl) resolve(window.acodePythonSdl);
 				else reject(new Error("sdl.js did not initialize"));
@@ -302,6 +304,9 @@ class Python {
 		this.$wrapBtn?.remove();
 		this.$status?.remove();
 		window.acodePythonSdl?.dispose?.();
+		// a later init loads a fresh sdl.js instead of the disposed one
+		this.#sdlPromise = null;
+		this.$sdlScript?.remove();
 		this.#worker?.terminate();
 		editorManager.off("switch-file", this.checkRunnable.bind(this));
 		editorManager.off("rename-file", this.checkRunnable.bind(this));

src/main.js

@@ -112,7 +112,6 @@ function unrouteRuntimeFetch() {
 
 function getRuntime(baseUrl) {
 	runtimePromise ??= (async () => {
-		routeRuntimeFetch(baseUrl);
 		const pyodide = await loadRuntime({
 			baseUrl,
 			stdout: (text) => handlers.stdout(text),
@@ -162,6 +161,9 @@ async function run(
 	{ baseUrl, canvas, stdout, stderr, showImage, width, pixelRatio },
 ) {
 	stop();
+	// every run, not only the first load: package downloads need the route
+	// too, and dispose() may have removed it while the runtime was cached
+	routeRuntimeFetch(baseUrl);
 	const run = { task: null, stopped: false };
 	current = run;
 	Object.assign(handlers, { stdout, stderr, showImage });
@@ -245,6 +247,9 @@ function stop() {
 function dispose() {
 	stop();
 	unrouteRuntimeFetch();
+	// let the runtime be freed instead of reused after a remount
+	runtimePromise = null;
+	runner = null;
 	if (self.acodePythonSdl === api) delete self.acodePythonSdl;
 }