Update app and tooling

node_modules/signal-exit/README.md

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+# signal-exit
+
+When you want to fire an event no matter how a process exits:
+
+- reaching the end of execution.
+- explicitly having `process.exit(code)` called.
+- having `process.kill(pid, sig)` called.
+- receiving a fatal signal from outside the process
+
+Use `signal-exit`.
+
+```js
+// Hybrid module, either works
+import { onExit } from 'signal-exit'
+// or:
+// const { onExit } = require('signal-exit')
+
+onExit((code, signal) => {
+  console.log('process exited!', code, signal)
+})
+```
+
+## API
+
+`remove = onExit((code, signal) => {}, options)`
+
+The return value of the function is a function that will remove
+the handler.
+
+Note that the function _only_ fires for signals if the signal
+would cause the process to exit. That is, there are no other
+listeners, and it is a fatal signal.
+
+If the global `process` object is not suitable for this purpose
+(ie, it's unset, or doesn't have an `emit` method, etc.) then the
+`onExit` function is a no-op that returns a no-op `remove` method.
+
+### Options
+
+- `alwaysLast`: Run this handler after any other signal or exit
+  handlers. This causes `process.emit` to be monkeypatched.
+
+### Browser Fallback
+
+The `'signal-exit/browser'` module is the same fallback shim that
+just doesn't do anything, but presents the same function
+interface.
+
+Patches welcome to add something that hooks onto
+`window.onbeforeunload` or similar, but it might just not be a
+thing that makes sense there.