Fix Docker deployment inputs

Include all addon workspaces and vendored dependencies in image builds, and expose deploy time plus commit metadata on the home page.

Amp-Thread-ID: https://ampcode.com/threads/T-01a033d4-0e44-708e-af0e-6166283416ff
Co-authored-by: Heaust Azure <heaust.azure@gmail.com>

server/app.go

@@ -13,6 +13,7 @@ import (
 	"path"
 	"strconv"
 	"strings"
+	"time"
 )
 
 //go:embed web
@@ -40,6 +41,13 @@ func newApplication(store *playgroundStore, packages map[string]memoryAsset, mon
 		if err != nil {
 			return nil, err
 		}
+		if name == "home.html" {
+			logMessage, err := json.Marshal(deploymentLogMessage())
+			if err != nil {
+				return nil, err
+			}
+			content = bytes.Replace(content, []byte("__YAWN_DEPLOYMENT_LOG__"), logMessage, 1)
+		}
 		pages[name] = content
 	}
 	return &application{
@@ -51,6 +59,22 @@ func newApplication(store *playgroundStore, packages map[string]memoryAsset, mon
 	}, nil
 }
 
+func deploymentLogMessage() string {
+	deployedAt := "unknown"
+	if value := os.Getenv("YAWN_DEPLOYED_AT"); value != "" {
+		deployedAt = value
+		if parsed, err := time.Parse(time.RFC3339, value); err == nil {
+			ist := time.FixedZone("IST", 5*60*60+30*60)
+			deployedAt = parsed.In(ist).Format("2 January 2006, 03:04:05 PM MST")
+		}
+	}
+	commitMessage := strings.TrimSpace(os.Getenv("YAWN_DEPLOY_COMMIT_MESSAGE"))
+	if commitMessage == "" {
+		commitMessage = "unknown"
+	}
+	return fmt.Sprintf("Yawn deployed at %s\nLatest commit: %s", deployedAt, commitMessage)
+}
+
 func (app *application) routes() http.Handler {
 	mux := http.NewServeMux()
 	mux.HandleFunc("/healthz", app.health)