Feat v0.9.2 Starlark converter consolidation + snapshot cleanup (#75)

Consolidate duplicate Go↔Starlark converters into sandbox/convert.go
and snapshot parsers into models/snapshot.go. Standardize snapshot
creation on wrapped format. Net -393 lines across 21 files.

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

server/workflow/automated.go

@@ -9,6 +9,7 @@ import (
 
 	"armature/events"
 	"armature/models"
+	"armature/sandbox"
 
 	"go.starlark.net/starlark"
 )
@@ -82,7 +83,7 @@ func (e *Engine) processAutomatedStage(ctx context.Context, inst *models.Workflo
 	// Parse stage_data into Starlark dict
 	var dataMap map[string]interface{}
 	if json.Unmarshal(inst.StageData, &dataMap) == nil {
-		_ = ctxDict.SetKey(starlark.String("stage_data"), goToStarlark(dataMap))
+		_ = ctxDict.SetKey(starlark.String("stage_data"), sandbox.GoToStarlark(dataMap))
 	} else {
 		_ = ctxDict.SetKey(starlark.String("stage_data"), starlark.NewDict(0))
 	}
@@ -128,7 +129,7 @@ func (e *Engine) handleHookResult(ctx context.Context, inst *models.WorkflowInst
 			var enrichedData json.RawMessage
 			if dataVal, found, _ := d.Get(starlark.String("data")); found {
 				if sd, ok := dataVal.(*starlark.Dict); ok {
-					goMap := starlarkDictToMap(sd)
+					goMap := sandbox.DictToMap(sd)
 					if data, err := json.Marshal(goMap); err == nil {
 						enrichedData = data
 					}
@@ -165,74 +166,3 @@ func parseHookRef(ref string) (string, string) {
 	return ref, "on_run"
 }
 
-// ── Starlark conversion helpers ─────────────
-
-func goToStarlark(v any) starlark.Value {
-	switch val := v.(type) {
-	case nil:
-		return starlark.None
-	case bool:
-		return starlark.Bool(val)
-	case float64:
-		if val == float64(int(val)) {
-			return starlark.MakeInt(int(val))
-		}
-		return starlark.Float(val)
-	case string:
-		return starlark.String(val)
-	case map[string]interface{}:
-		d := starlark.NewDict(len(val))
-		for k, v := range val {
-			_ = d.SetKey(starlark.String(k), goToStarlark(v))
-		}
-		return d
-	case []interface{}:
-		elems := make([]starlark.Value, len(val))
-		for i, v := range val {
-			elems[i] = goToStarlark(v)
-		}
-		return starlark.NewList(elems)
-	default:
-		return starlark.String(fmt.Sprintf("%v", v))
-	}
-}
-
-func starlarkDictToMap(d *starlark.Dict) map[string]any {
-	result := make(map[string]any, d.Len())
-	for _, item := range d.Items() {
-		k, ok := item[0].(starlark.String)
-		if !ok {
-			continue
-		}
-		result[string(k)] = starlarkToGo(item[1])
-	}
-	return result
-}
-
-func starlarkToGo(v starlark.Value) any {
-	switch val := v.(type) {
-	case starlark.NoneType:
-		return nil
-	case starlark.Bool:
-		return bool(val)
-	case starlark.Int:
-		if i, ok := val.Int64(); ok {
-			return i
-		}
-		return val.String()
-	case starlark.Float:
-		return float64(val)
-	case starlark.String:
-		return string(val)
-	case *starlark.List:
-		result := make([]any, val.Len())
-		for i := 0; i < val.Len(); i++ {
-			result[i] = starlarkToGo(val.Index(i))
-		}
-		return result
-	case *starlark.Dict:
-		return starlarkDictToMap(val)
-	default:
-		return v.String()
-	}
-}

server/workflow/engine.go

@@ -18,25 +18,6 @@ import (
 // MaxConsecutiveAutomated is the cycle guard limit for automated stages.
 const MaxConsecutiveAutomated = 10
 
-// parseSnapshotStages handles both snapshot formats:
-//   - Wrapped:  {"stages": [...], "workflow": {...}}  (from Publish handler)
-//   - Legacy:   [...]                                  (from early tests)
-func parseSnapshotStages(raw json.RawMessage) ([]models.WorkflowStage, error) {
-	// Try wrapped format first
-	var wrapped struct {
-		Stages []models.WorkflowStage `json:"stages"`
-	}
-	if err := json.Unmarshal(raw, &wrapped); err == nil && len(wrapped.Stages) > 0 {
-		return wrapped.Stages, nil
-	}
-	// Fallback to flat array
-	var stages []models.WorkflowStage
-	if err := json.Unmarshal(raw, &stages); err != nil {
-		return nil, fmt.Errorf("corrupt version snapshot: %w", err)
-	}
-	return stages, nil
-}
-
 // Engine orchestrates workflow instance lifecycle.
 type Engine struct {
 	stores store.Stores
@@ -64,7 +45,7 @@ func (e *Engine) Start(ctx context.Context, workflowID string, initialData json.
 		return nil, fmt.Errorf("no published version: %w", err)
 	}
 
-	stages, err := parseSnapshotStages(ver.Snapshot)
+	stages, err := models.ParseSnapshotStages(ver.Snapshot)
 	if err != nil {
 		return nil, err
 	}
@@ -142,7 +123,7 @@ func (e *Engine) advanceInternal(ctx context.Context, instanceID string, stageDa
 		return nil, fmt.Errorf("version not found: %w", err)
 	}
 
-	stages, err := parseSnapshotStages(ver.Snapshot)
+	stages, err := models.ParseSnapshotStages(ver.Snapshot)
 	if err != nil {
 		return nil, err
 	}
@@ -348,7 +329,7 @@ func (e *Engine) AdvancePublic(ctx context.Context, entryToken string, stageData
 	if err != nil {
 		return nil, fmt.Errorf("version not found: %w", err)
 	}
-	stages, err := parseSnapshotStages(ver.Snapshot)
+	stages, err := models.ParseSnapshotStages(ver.Snapshot)
 	if err != nil {
 		return nil, err
 	}
@@ -383,7 +364,7 @@ func (e *Engine) SubmitSignoff(ctx context.Context, instanceID, userID, decision
 	if err != nil {
 		return nil, fmt.Errorf("version not found: %w", err)
 	}
-	stages, err := parseSnapshotStages(ver.Snapshot)
+	stages, err := models.ParseSnapshotStages(ver.Snapshot)
 	if err != nil {
 		return nil, err
 	}
@@ -448,7 +429,7 @@ func CheckClaimRole(ctx context.Context, stores store.Stores, assignment *models
 	if err != nil {
 		return nil
 	}
-	stages, parseErr := parseSnapshotStages(ver.Snapshot)
+	stages, parseErr := models.ParseSnapshotStages(ver.Snapshot)
 	if parseErr != nil {
 		return nil
 	}

server/workflow/scanner.go

@@ -91,7 +91,7 @@ func (sc *Scanner) runScan() {
 		if err != nil {
 			return nil
 		}
-		stages, parseErr := parseSnapshotStages(v.Snapshot)
+		stages, parseErr := models.ParseSnapshotStages(v.Snapshot)
 		if parseErr != nil {
 			return nil
 		}