Refactor repository. Fixes #2161 (#2192)

* Remove duplicate LICENSE.
* Remove un-userd pyscript.sw directory and its content.
* Remove ReadTheDocs settings (unused).
* Remove un-used pyproject.toml
* Remove now unused CHANGELOG. Changes now tracked via release notes on GitHub.
* Updated / cleaned release page template and associated GH actions.
* Update prettierignore to remove un-needed refs.
* Move troubleshooting into correct README.
* Add reason for the index.html
* Rename the "pyscript.core" directory to "core".
* Update PR template because CHANGELOG is no longer used.
* Codespell configuration in pyproject.toml.
* Update pyscript.core -> core in .githubignore
* Remove test-results/.last-run.json. This should be ignored by git.
* Pin nodejs version.

---------

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

core/src/plugins/py-terminal/py.js

@@ -0,0 +1,179 @@
+// PyScript py-terminal plugin
+import { hooks } from "../../core.js";
+import { defineProperties } from "polyscript/exports";
+
+const bootstrapped = new WeakSet();
+
+// this callback will be serialized as string and it never needs
+// to be invoked multiple times. Each xworker here is bootstrapped
+// only once thanks to the `sync.is_pyterminal()` check.
+const workerReady = ({ interpreter, io, run, type }, { sync }) => {
+    if (type !== "py" || !sync.is_pyterminal()) return;
+
+    run(
+        [
+            "from polyscript import currentScript as _",
+            "__terminal__ = _.terminal",
+            "del _",
+        ].join(";"),
+    );
+
+    let data = "";
+    const { pyterminal_read, pyterminal_write } = sync;
+    const decoder = new TextDecoder();
+    const generic = {
+        isatty: false,
+        write(buffer) {
+            data = decoder.decode(buffer);
+            pyterminal_write(data);
+            return buffer.length;
+        },
+    };
+
+    io.stderr = (error) => {
+        pyterminal_write(String(error.message || error));
+    };
+
+    interpreter.setStdout(generic);
+    interpreter.setStderr(generic);
+    interpreter.setStdin({
+        isatty: false,
+        stdin: () => pyterminal_read(data),
+    });
+};
+
+export default async (element) => {
+    // lazy load these only when a valid terminal is found
+    const [{ Terminal }, { Readline }, { FitAddon }, { WebLinksAddon }] =
+        await Promise.all([
+            import(/* webpackIgnore: true */ "../../3rd-party/xterm.js"),
+            import(
+                /* webpackIgnore: true */ "../../3rd-party/xterm-readline.js"
+            ),
+            import(
+                /* webpackIgnore: true */ "../../3rd-party/xterm_addon-fit.js"
+            ),
+            import(
+                /* webpackIgnore: true */ "../../3rd-party/xterm_addon-web-links.js"
+            ),
+        ]);
+
+    const readline = new Readline();
+
+    // common main thread initialization for both worker
+    // or main case, bootstrapping the terminal on its target
+    const init = (options) => {
+        let target = element;
+        const selector = element.getAttribute("target");
+        if (selector) {
+            target =
+                document.getElementById(selector) ||
+                document.querySelector(selector);
+            if (!target) throw new Error(`Unknown target ${selector}`);
+        } else {
+            target = document.createElement("py-terminal");
+            target.style.display = "block";
+            element.after(target);
+        }
+        const terminal = new Terminal({
+            theme: {
+                background: "#191A19",
+                foreground: "#F5F2E7",
+            },
+            ...options,
+        });
+        const fitAddon = new FitAddon();
+        terminal.loadAddon(fitAddon);
+        terminal.loadAddon(readline);
+        terminal.loadAddon(new WebLinksAddon());
+        terminal.open(target);
+        fitAddon.fit();
+        terminal.focus();
+        defineProperties(element, {
+            terminal: { value: terminal },
+            process: {
+                value: async (code) => {
+                    for (const line of code.split(/(?:\r\n|\r|\n)/)) {
+                        terminal.paste(`${line}`);
+                        terminal.write("\r\n");
+                        do {
+                            await new Promise((resolve) =>
+                                setTimeout(resolve, 0),
+                            );
+                        } while (!readline.activeRead?.resolve);
+                        readline.activeRead.resolve(line);
+                    }
+                },
+            },
+        });
+        return terminal;
+    };
+
+    // branch logic for the worker
+    if (element.hasAttribute("worker")) {
+        // add a hook on the main thread to setup all sync helpers
+        // also bootstrapping the XTerm target on main *BUT* ...
+        hooks.main.onWorker.add(function worker(_, xworker) {
+            // ... as multiple workers will add multiple callbacks
+            // be sure no xworker is ever initialized twice!
+            if (bootstrapped.has(xworker)) return;
+            bootstrapped.add(xworker);
+
+            // still cleanup this callback for future scripts/workers
+            hooks.main.onWorker.delete(worker);
+
+            init({
+                disableStdin: false,
+                cursorBlink: true,
+                cursorStyle: "block",
+            });
+
+            xworker.sync.is_pyterminal = () => true;
+            xworker.sync.pyterminal_read = readline.read.bind(readline);
+            xworker.sync.pyterminal_write = readline.write.bind(readline);
+        });
+
+        // setup remote thread JS/Python code for whenever the
+        // worker is ready to become a terminal
+        hooks.worker.onReady.add(workerReady);
+    } else {
+        // in the main case, just bootstrap XTerm without
+        // allowing any input as that's not possible / awkward
+        hooks.main.onReady.add(function main({ interpreter, io, run, type }) {
+            if (type !== "py") return;
+
+            console.warn("py-terminal is read only on main thread");
+            hooks.main.onReady.delete(main);
+
+            // on main, it's easy to trash and clean the current terminal
+            globalThis.__py_terminal__ = init({
+                disableStdin: true,
+                cursorBlink: false,
+                cursorStyle: "underline",
+            });
+            run("from js import __py_terminal__ as __terminal__");
+            delete globalThis.__py_terminal__;
+
+            io.stderr = (error) => {
+                readline.write(String(error.message || error));
+            };
+
+            let data = "";
+            const decoder = new TextDecoder();
+            const generic = {
+                isatty: false,
+                write(buffer) {
+                    data = decoder.decode(buffer);
+                    readline.write(data);
+                    return buffer.length;
+                },
+            };
+            interpreter.setStdout(generic);
+            interpreter.setStderr(generic);
+            interpreter.setStdin({
+                isatty: false,
+                stdin: () => readline.read(data),
+            });
+        });
+    }
+};