Bsky link card service (#4547)

* setup bskycard

* quick proof of concept for png card generation

* bskycard: use jsx

* bskycard: 3x5 profile layout

* bskycard: add butterfly overlay

* bskycard: tidy

* bskycard: separate and reorganize

* bskycard: tidy

* bskycard: tidy

* bskycard: tidy

* bskycard: poc of transparent overlay and box shadow

* bskycard: reorg impl into src/ directory

* bskycard: use more standard app structure

* bskycard: setup dockerfile, fix build

* bskycard: support for x-origin-verify

* bskycard: card layout, filter images based on labels

* bskycard: tidy

* bskycard: support cluster mode

* bskycard: handle error fetching starter pack info

* bskycard: tidy

* bskycard: fix leak on failed image fetch

* bskycard: build workflow

* bskyogcard: rename from bskycard

* bskyogcard: fix some express plumbing

* bskyogcard: add cdn tags, tidy

bskyogcard/src/components/Img.tsx

@@ -0,0 +1,10 @@
+import React from 'react'
+
+export function Img(
+  props: Omit<React.ImgHTMLAttributes<HTMLImageElement>, 'src'> & {src: Buffer},
+) {
+  const {src, ...others} = props
+  return (
+    <img {...others} src={`data:image/jpeg;base64,${src.toString('base64')}`} />
+  )
+}