web: fix markdown rendering bug for alerts (#9037)

* web: fix esbuild issue with style sheets

Getting ESBuild, Lit, and Storybook to all agree on how to read and parse stylesheets is a serious
pain. This fix better identifies the value types (instances) being passed from various sources in
the repo to the three *different* kinds of style processors we're using (the native one, the
polyfill one, and whatever the heck Storybook does internally).

Falling back to using older CSS instantiating techniques one era at a time seems to do the trick.
It's ugly, but in the face of the aggressive styling we use to avoid Flashes of Unstyled Content
(FLoUC), it's the logic with which we're left.

In standard mode, the following warning appears on the console when running a Flow:

```
Autofocus processing was blocked because a document already has a focused element.
```

In compatibility mode, the following **error** appears on the console when running a Flow:

```
crawler-inject.js:1106 Uncaught TypeError: Failed to execute 'observe' on 'MutationObserver': parameter 1 is not of type 'Node'.
    at initDomMutationObservers (crawler-inject.js:1106:18)
    at crawler-inject.js:1114:24
    at Array.forEach (<anonymous>)
    at initDomMutationObservers (crawler-inject.js:1114:10)
    at crawler-inject.js:1549:1
initDomMutationObservers @ crawler-inject.js:1106
(anonymous) @ crawler-inject.js:1114
initDomMutationObservers @ crawler-inject.js:1114
(anonymous) @ crawler-inject.js:1549
```

Despite this error, nothing seems to be broken and flows work as anticipated.

* web:fix markdown rendering bug for alerts

The move to using showdown dynamically, at run-time, resulted in a parse error
where our alerts were not being decorated with the right syntax. This patch
recognizes the new `:::info` EOL syntax (and leaves the old one in-place, as
well) and the rendering is now correct.

Our complexity has reached the point where eslint now needs the memory increase.

web/src/elements/Markdown.ts

@@ -56,7 +56,7 @@ export class Markdown extends AKElement {
     converter = new showdown.Converter({ metadata: true, tables: true });
 
     replaceAdmonitions(input: string): string {
-        const admonitionStart = /:::(\w+)<br\s\/>/gm;
+        const admonitionStart = /:::(\w+)(<br\s*\/>|\s*$)/gm;
         const admonitionEnd = /:::/gm;
         return (
             input