Add welcome surface and user default surface preference

- Create welcome surface: topbar + getting-started card shown when
  no extension surfaces are installed. Admins see a link to Packages,
  non-admins see a message to contact their administrator.
- Update resolveDefaultSurface priority chain:
  user preference → global config → first extension → /welcome
- Register welcome as a core surface with authenticated auth
- Final fallback is now /welcome instead of /admin, breaking the
  infinite back-button loop

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/pages/pages.go

@@ -244,6 +244,11 @@ func (e *Engine) registerCoreSurfaces() {
 			Title: "Workflow Landing", Template: "workflow-landing", Auth: "public",
 			Layout: "single", Source: "core",
 		},
+		{
+			ID: "welcome", Route: "/welcome",
+			Title: "Welcome", Template: "surface-welcome", Auth: "authenticated",
+			Layout: "single", Source: "core",
+		},
 	}
 }
 

server/pages/pages_surfaces.go

@@ -91,22 +91,35 @@ func (e *Engine) EnabledSurfaceIDs() []string {
 
 // DefaultSurfaceRedirect returns a handler for GET / that redirects to the
 // configured default surface, falling back to the first enabled extension
-// surface, then /admin.
+// surface, then /welcome.
 func (e *Engine) DefaultSurfaceRedirect() gin.HandlerFunc {
 	return func(c *gin.Context) {
-		target := e.resolveDefaultSurface(c.Request.Context())
+		userID := c.GetString("user_id")
+		target := e.resolveDefaultSurface(c.Request.Context(), userID)
 		c.Redirect(http.StatusTemporaryRedirect, e.cfg.BasePath+target)
 	}
 }
 
 // resolveDefaultSurface returns the path to redirect to (without BasePath).
-// Priority: configured default_surface → first enabled extension surface → /admin.
-func (e *Engine) resolveDefaultSurface(ctx context.Context) string {
+// Priority: user preference → global default_surface → first enabled extension → /welcome.
+func (e *Engine) resolveDefaultSurface(ctx context.Context, userID string) string {
 	if e.stores.GlobalConfig == nil || e.stores.Packages == nil {
-		return "/admin"
+		return "/welcome"
 	}
 
-	// 1. Check configured default_surface
+	// 1. Check user preference (default_surface in user settings)
+	if userID != "" && e.stores.Users != nil {
+		if user, err := e.stores.Users.GetByID(ctx, userID); err == nil && user != nil {
+			if id, _ := user.Settings["default_surface"].(string); id != "" {
+				if path := e.surfacePath(ctx, id); path != "" {
+					return path
+				}
+				// User's chosen surface is missing or disabled — fall through
+			}
+		}
+	}
+
+	// 2. Check admin-configured global default_surface
 	if raw, err := e.stores.GlobalConfig.Get(ctx, "default_surface"); err == nil && raw != nil {
 		if id, ok := raw["id"].(string); ok && id != "" {
 			if path := e.surfacePath(ctx, id); path != "" {
@@ -116,7 +129,7 @@ func (e *Engine) resolveDefaultSurface(ctx context.Context) string {
 		}
 	}
 
-	// 2. First enabled extension surface
+	// 3. First enabled extension surface
 	surfaces, err := e.stores.Packages.ListEnabledByType(ctx, "surface")
 	if err == nil {
 		for _, s := range surfaces {
@@ -129,8 +142,8 @@ func (e *Engine) resolveDefaultSurface(ctx context.Context) string {
 		}
 	}
 
-	// 3. Fallback
-	return "/admin"
+	// 4. Fallback — welcome surface (no extensions installed)
+	return "/welcome"
 }
 
 // surfacePath returns the URL path for a surface ID, or "" if the surface
@@ -155,9 +168,8 @@ func (e *Engine) surfacePath(ctx context.Context, id string) string {
 	return "/s/" + id
 }
 
-// disabledRedirect returns a handler that redirects to /admin.
-// Uses /admin (not /) to avoid a redirect loop when the default surface
-// is the one being disabled.
+// disabledRedirect returns a handler that redirects to /.
+// The DefaultSurfaceRedirect handler will resolve to the appropriate surface.
 func (e *Engine) disabledRedirect() gin.HandlerFunc {
 	return func(c *gin.Context) {
 		c.Redirect(http.StatusTemporaryRedirect, e.cfg.BasePath+"/admin")

server/pages/templates/base.html

@@ -89,6 +89,7 @@
         {{if eq .Surface "admin"}}{{template "surface-admin" .}}
         {{else if eq .Surface "team-admin"}}{{template "surface-team-admin" .}}
         {{else if eq .Surface "settings"}}{{template "surface-settings" .}}
+        {{else if eq .Surface "welcome"}}{{template "surface-welcome" .}}
         {{else if and .Manifest (eq .Manifest.Source "extension")}}{{template "surface-extension" .}}
         {{else}}<div style="padding:20px">Unknown surface: {{.Surface}}</div>
         {{end}}
@@ -123,6 +124,7 @@
     {{if eq .Surface "admin"}}{{template "scripts-admin" .}}{{end}}
     {{if eq .Surface "team-admin"}}{{template "scripts-team-admin" .}}{{end}}
     {{if eq .Surface "settings"}}{{template "scripts-settings" .}}{{end}}
+    {{if eq .Surface "welcome"}}{{template "scripts-welcome" .}}{{end}}
     {{/* v0.27.0: Extension surface JS — loaded from /surfaces/{id}/js/main.js */}}
     {{if and .Manifest (eq .Manifest.Source "extension")}}
     <script type="module" nonce="{{.CSPNonce}}" src="{{.BasePath}}/surfaces/{{.Surface}}/js/main.js?v={{.Version}}"></script>

server/pages/templates/surfaces/welcome.html

@@ -0,0 +1,25 @@
+{{/*
+    Welcome surface — shown when no extension surfaces are installed.
+    Renders topbar + welcome card with getting-started info.
+*/}}
+
+{{define "surface-welcome"}}
+<div id="welcome-mount" style="display:flex;flex-direction:column;height:100%;"></div>
+{{end}}
+
+{{define "scripts-welcome"}}
+<script type="module" nonce="{{.CSPNonce}}">
+    const { h, render } = await import('{{.BasePath}}/js/sw/vendor/preact.module.js');
+    const hooksModule = await import('{{.BasePath}}/js/sw/vendor/hooks.module.js');
+    const { default: htm } = await import('{{.BasePath}}/js/sw/vendor/htm.module.js');
+    const html = htm.bind(h);
+    window.preact = window.preact || { h, render };
+    window.hooks = window.hooks || hooksModule;
+    window.html = window.html || html;
+
+    const { boot } = await import('{{.BasePath}}/js/sw/sdk/index.js?v={{.Version}}');
+    await boot();
+
+    await import('{{.BasePath}}/js/sw/surfaces/welcome/index.js?v={{.Version}}');
+</script>
+{{end}}