loop/webui: swtich to web components impl (#1)

* loop/webui: swtich to web components impl

This change reorganizes the original vibe-coded
frontend code into a structure that's much
easier for a human to read and reason about,
while retaining the user-visible functionality
of its vibe-coded predecessor. Perhaps most
importantly, this change makes the code testable.

Some other notable details:

This does not use any of the popular large web
frameworks, but instead follows more of an
"a la carte" approach: leverage features
that already exist in modern web browsers,
like custom elements and shadow DOM.

Templating and basic component lifecycle
management are provided by lit.

State management is nothing fancy. It
doesn't use any library or framework, just
a basic "Events up, properties down"
approach.

* fix bad esbuild.go merge

* loop/webui: don't bundle src/web-components/demo

* loop/webui: don't 'npm ci' dev deps in the container

* rebase to main, undo README.md changes, add webuil.Build() call to LaunchContainer()
diff --git a/loop/webui/readme.md b/loop/webui/readme.md
index 861a8cd..b904934 100644
--- a/loop/webui/readme.md
+++ b/loop/webui/readme.md
@@ -49,3 +49,14 @@
 - `dist/`: Generated JavaScript bundle
 - `esbuild.go`: Go code for bundling TypeScript files
 - `Makefile`: Build tasks
+
+## Bundle Analysis
+
+You can analyze the size and dependency structure of the TypeScript bundles:
+
+```bash
+# Generate bundle metafiles in a temporary directory
+go run sketch.dev/cmd/bundle-analyzer
+```
+
+The tool generates metafiles that can be analyzed by dragging them onto the esbuild analyzer at https://esbuild.github.io/analyze/