Remove @astrojs/lit (#11680)

* Remove @astrojs/lit

This removes the Lit integration as an official integration. The reasons
for doing so in 5.0:

- Only 1% of Astro users use this integration.
- SSR support in Lit is at a lower-level of support due to be a Labs
project: https://lit.dev/docs/libraries/labs/, and has been in this
state since we added support a couple of years ago.
- The maintenance cost of fixing bugs in this integration is too high
given the low usage. Some PRs for upgrading Lit versions have taken
quite a long time. We can't justify the core team being responsible for
this going forward.
- There used to be community contributions to fix bugs but this has
fallen off for various reasons.

Given that, this PR removes the integration as one that is officially
supported by the Astro core team. Interested community members are
encouraged to fork the integration and continue the development in
another repository.

* Remove e2e tests and examples

* Update lockfile

* Remove ssr-lit.test.js

* Remove error for no client entrypoint

* Remove auto selection of the Lit renderer

* Remove lit package.json

* Remove lit fixture

2 files changed, 0 insertions, 139 deletions

diff --git a/packages/integrations/lit/src/client.ts b/packages/integrations/lit/src/client.ts
deleted file mode 100644
index 9a573d8ee..000000000
--- a/packages/integrations/lit/src/client.ts
+++ /dev/null
@@ -1,72 +0,0 @@
-/**
- * Adds the appropriate slot attribute to each top-level node in the given HTML
- * string.
- *
- * @example
- * addSlotAttrsToHtmlString('foo', '<div>bar</div><div>baz</div>');
- * // '<div slot="foo">bar</div><div slot="foo">baz</div>'
- *
- * @param slotName Name of slot to apply to HTML string.
- * @param html Stringified HTML that should be projected into the given slotname.
- * @returns A stringified HTML string with the slot attribute applied to each top-level node.
- */
-const addSlotAttrsToHtmlString = (slotName: string, html: string) => {
-	const templ = document.createElement('template');
-	templ.innerHTML = html;
-	Array.from(templ.content.children).forEach((node) => {
-		node.setAttribute('slot', slotName);
-	});
-	return templ.innerHTML;
-};
-
-export default (element: HTMLElement) =>
-	async (
-		Component: any,
-		props: Record<string, any>,
-		{ default: defaultChildren, ...slotted }: { default: string; [slotName: string]: string },
-	) => {
-		// Get the LitElement element instance.
-		let component = element.children[0];
-		// Check if hydration model is client:only
-		const isClientOnly = element.getAttribute('client') === 'only';
-
-		// We need to attach the element and it's children to the DOM since it's not
-		// SSR'd.
-		if (isClientOnly) {
-			component = new Component();
-
-			const otherSlottedChildren = Object.entries(slotted)
-				.map(([slotName, htmlStr]) => addSlotAttrsToHtmlString(slotName, htmlStr))
-				.join('');
-
-			// defaultChildren can actually be undefined, but TS will complain if we
-			// type it as so, make sure we don't render undefined.
-			component.innerHTML = `${defaultChildren ?? ''}${otherSlottedChildren}`;
-			element.appendChild(component);
-
-			// Set props bound to non-reactive properties as attributes.
-			for (let [name, value] of Object.entries(props)) {
-				if (!(name in Component.prototype)) {
-					component.setAttribute(name, value);
-				}
-			}
-		}
-
-		// If there is no deferral of hydration, then all reactive properties are
-		// already serialized as reflected attributes, or no reactive props were set
-		// Alternatively, if hydration is client:only proceed to set props.
-		if (!component || !(component.hasAttribute('defer-hydration') || isClientOnly)) {
-			return;
-		}
-
-		// Set properties on the LitElement instance for resuming hydration.
-		for (let [name, value] of Object.entries(props)) {
-			// Check if reactive property or class property.
-			if (name in Component.prototype) {
-				(component as any)[name] = value;
-			}
-		}
-
-		// Tell LitElement to resume hydration.
-		component.removeAttribute('defer-hydration');
-	};
diff --git a/packages/integrations/lit/src/index.ts b/packages/integrations/lit/src/index.ts
deleted file mode 100644
index 94a6d683a..000000000
--- a/packages/integrations/lit/src/index.ts
+++ /dev/null
@@ -1,67 +0,0 @@
-import { readFileSync } from 'node:fs';
-import type { AstroIntegration, ContainerRenderer } from 'astro';
-
-function getViteConfiguration() {
-	return {
-		optimizeDeps: {
-			include: [
-				'@astrojs/lit/dist/client.js',
-				'@astrojs/lit/client-shim.js',
-				'@astrojs/lit/hydration-support.js',
-				'@webcomponents/template-shadowroot/template-shadowroot.js',
-				'@lit-labs/ssr-client/lit-element-hydrate-support.js',
-			],
-			exclude: ['@astrojs/lit/server.js'],
-		},
-		ssr: {
-			external: ['lit-element', '@lit-labs/ssr', '@astrojs/lit', 'lit/decorators.js'],
-		},
-	};
-}
-
-export function getContainerRenderer(): ContainerRenderer {
-	return {
-		name: '@astrojs/lit',
-		serverEntrypoint: '@astrojs/lit/server.js',
-	};
-}
-
-export default function (): AstroIntegration {
-	return {
-		name: '@astrojs/lit',
-		hooks: {
-			'astro:config:setup': ({ updateConfig, addRenderer, injectScript }) => {
-				// Inject the necessary polyfills on every page (inlined for speed).
-				injectScript(
-					'head-inline',
-					readFileSync(new URL('../client-shim.min.js', import.meta.url), { encoding: 'utf-8' }),
-				);
-				// Inject the hydration code, before a component is hydrated.
-				injectScript('before-hydration', `import '@astrojs/lit/hydration-support.js';`);
-				// Add the lit renderer so that Astro can understand lit components.
-				addRenderer({
-					name: '@astrojs/lit',
-					serverEntrypoint: '@astrojs/lit/server.js',
-					clientEntrypoint: '@astrojs/lit/dist/client.js',
-				});
-				// Update the vite configuration.
-				updateConfig({
-					vite: getViteConfiguration(),
-				});
-			},
-			'astro:build:setup': ({ vite, target }) => {
-				if (target === 'server') {
-					if (!vite.ssr) {
-						vite.ssr = {};
-					}
-					if (!vite.ssr.noExternal) {
-						vite.ssr.noExternal = [];
-					}
-					if (Array.isArray(vite.ssr.noExternal)) {
-						vite.ssr.noExternal.push('lit');
-					}
-				}
-			},
-		},
-	};
-}