Add Go CDN and playground server

Build Core and Handles into in-memory CDN modules, add the marketing site and tutorial docs, and provide a SQLite-backed WebGPU playground with TypeScript tooling and profiling.

Amp-Thread-ID: https://ampcode.com/threads/T-01a02485-5574-707c-bff4-5668d83bee8a
Co-authored-by: Heaust Azure <heaust.azure@gmail.com>

server/packages.go

@@ -0,0 +1,105 @@
+package main
+
+import (
+	"bytes"
+	"crypto/sha256"
+	"fmt"
+	"io/fs"
+	"mime"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"time"
+)
+
+type memoryAsset struct {
+	contentType string
+	content     []byte
+	etag        string
+	modified    time.Time
+}
+
+func buildPackages(root string) (map[string]memoryAsset, error) {
+	output, err := os.MkdirTemp("", "yawn-packages-*")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(output)
+
+	if err := runBuild(root, "wasm-pack", "build", filepath.Join(root, "core"),
+		"--target", "web", "--out-dir", filepath.Join(output, "pkg"), "--release"); err != nil {
+		return nil, err
+	}
+	if err := runBuild(root, "node", filepath.Join(root, "server", "build.mjs"), root, output); err != nil {
+		return nil, err
+	}
+
+	assets := make(map[string]memoryAsset)
+	for _, name := range []string{
+		"core.js",
+		"handles.js",
+		"worker.js",
+		"importer-worker.js",
+		"bvh-worker.js",
+	} {
+		asset, err := loadMemoryAsset(filepath.Join(output, name))
+		if err != nil {
+			return nil, err
+		}
+		assets[name] = asset
+	}
+
+	err = filepath.WalkDir(filepath.Join(output, "pkg"), func(path string, entry fs.DirEntry, walkErr error) error {
+		if walkErr != nil {
+			return walkErr
+		}
+		if entry.IsDir() {
+			return nil
+		}
+		relative, err := filepath.Rel(filepath.Join(output, "pkg"), path)
+		if err != nil {
+			return err
+		}
+		asset, err := loadMemoryAsset(path)
+		if err != nil {
+			return err
+		}
+		assets[filepath.ToSlash(filepath.Join("pkg", relative))] = asset
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+	return assets, nil
+}
+
+func runBuild(directory, name string, arguments ...string) error {
+	command := exec.Command(name, arguments...)
+	command.Dir = directory
+	command.Env = os.Environ()
+	var output bytes.Buffer
+	command.Stdout = &output
+	command.Stderr = &output
+	if err := command.Run(); err != nil {
+		return fmt.Errorf("%s: %w\n%s", name, err, output.String())
+	}
+	return nil
+}
+
+func loadMemoryAsset(path string) (memoryAsset, error) {
+	content, err := os.ReadFile(path)
+	if err != nil {
+		return memoryAsset{}, err
+	}
+	digest := sha256.Sum256(content)
+	contentType := mime.TypeByExtension(filepath.Ext(path))
+	if contentType == "" {
+		contentType = "application/octet-stream"
+	}
+	return memoryAsset{
+		contentType: contentType,
+		content:     content,
+		etag:        fmt.Sprintf("\"%x\"", digest[:12]),
+		modified:    time.Now().UTC(),
+	}, nil
+}