Feat v0.3.6 demo workflows + interactive demo

Four example workflow packages proving the engine end-to-end:
- Bug Report Triage: public entry, branch routing, SLA timer
- Employee Onboarding: Starlark automated stages, signoff gate
- Content Approval: multi-party signoff, revision cycle loop
- Webhook Notifier: http.post, connections fallback, delivery logging

Demo surface at /s/workflow-demo with cards, stage diagrams, Starlark
viewer, API examples, active/published status, and copyable public links.

Engine fixes: started_by in automated context, sla_seconds in package
installer, parseSnapshotStages for wrapped/legacy formats.

Platform fixes: extension SDK boot in base.html (Preact globals + boot()),
admin teams paginated response extraction, workflow adoption endpoint
(POST /teams/:teamId/workflows/:id/adopt), team-admin copyable link.

Review pass remains on roadmap for remaining UI polish.

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

server/handlers/workflow_packages.go

@@ -67,6 +67,9 @@ func (h *WorkflowPackageHandler) ExportWorkflowPackage(c *gin.Context) {
 		if s.StarlarkHook != nil {
 			sd["starlark_hook"] = *s.StarlarkHook
 		}
+		if s.SLASeconds != nil {
+			sd["sla_seconds"] = *s.SLASeconds
+		}
 		if len(s.FormTemplate) > 0 && string(s.FormTemplate) != "{}" {
 			var ft any
 			if json.Unmarshal(s.FormTemplate, &ft) == nil {
@@ -225,6 +228,7 @@ func InstallWorkflowFromManifest(ctx *gin.Context, stores store.Stores, pkgID st
 			AssignmentTeamID: s.AssignmentTeamID,
 			SurfacePkgID:     s.SurfacePkgID,
 			StarlarkHook:     s.StarlarkHook,
+			SLASeconds:       s.SLASeconds,
 		}
 		if st.StageMode == "" {
 			st.StageMode = models.StageModeDelegated
@@ -268,6 +272,7 @@ type workflowPkgStage struct {
 	AssignmentTeamID *string `json:"assignment_team_id,omitempty"`
 	SurfacePkgID     *string `json:"surface_pkg_id,omitempty"`
 	StarlarkHook     *string `json:"starlark_hook,omitempty"`
+	SLASeconds       *int    `json:"sla_seconds,omitempty"`
 	FormTemplate     any     `json:"form_template,omitempty"`
 	StageConfig      any     `json:"stage_config,omitempty"`
 	BranchRules      any     `json:"branch_rules,omitempty"`