rebased embedr (#3511)

* skeleton of embedr service, based on bskyweb

* embedr container setup

* builds on this branch

* actual routes

* fix embedr go:embed

* tweak embedr dockerfile

* progress on embedr

* fix path params

* tweaks to build process

* try to get embedr dockerfile to install embed deps

* build this branch

* updates to match sam's output HTML

* try to unbreak embedr dockerfile

* small embedr tweak

* docker hack

* get embed.js copied over to embedr

* don't x-frame-options for embed.bsky.app

* bskyembed: remove a console.log

* use html/template for golang snippet generation

* simplify embedr API fetches

* missing file

* Rm console.log fully

---------

Co-authored-by: Dan Abramov <dan.abramov@gmail.com>

bskyweb/cmd/embedr/render.go

@@ -0,0 +1,16 @@
+package main
+
+import (
+	"html/template"
+	"io"
+
+	"github.com/labstack/echo/v4"
+)
+
+type Template struct {
+	templates *template.Template
+}
+
+func (t *Template) Render(w io.Writer, name string, data interface{}, c echo.Context) error {
+	return t.templates.ExecuteTemplate(w, name, data)
+}