Topdata Migration (#2)

Native topdata migration summary

- Replaced the legacy 2dabuilder runtime path with the native topdata builder.
- Native build, validate, compare, and convert flows now cover the canonical topdata pipeline.
- compare-topdata is now a native self-check; legacy reference-builder runtime usage was removed.
- Parts generation follows the native asset-scan contract and uses sow-assets via project asset resolution.
- Generated feat families, class-feat injects, masterfeat/successor expansion, and dataset-derived feat generation were brought to parity and regression-covered.
- Remaining mirrored datasets were migrated into native-owned canonical data while preserving lock IDs.
- normalize-topdata bridge behavior and migration-era ownership markers were removed.
- Documentation was rewritten around the native workflow and active contracts were cleaned up.
- Final hardening pass removed stale validator assumptions and cleaned ignored/generated artifacts for PR readiness.

Reviewed-on: https://gitea.westgate.pw/ShadowsOverWestgate/sow-tools/pulls/2
Co-authored-by: vickydotbat <vickydotbat@tutamail.com>
Co-committed-by: vickydotbat <vickydotbat@tutamail.com>

internal/project/project.go

@@ -36,9 +36,9 @@ type Config struct {
 }
 
 type ModuleConfig struct {
-	Name        string `json:"name"`
-	ResRef      string `json:"resref"`
-	Description string `json:"description"`
+	Name        string   `json:"name"`
+	ResRef      string   `json:"resref"`
+	Description string   `json:"description"`
 	HAKOrder    []string `json:"hak_order"`
 }
 
@@ -60,6 +60,7 @@ type TopDataConfig struct {
 	Source           string `json:"source"`
 	Build            string `json:"build"`
 	ReferenceBuilder string `json:"reference_builder"`
+	Assets           string `json:"assets"`
 }
 
 type Inventory struct {
@@ -251,6 +252,37 @@ func (p *Project) TopDataReferenceBuilderDir() string {
 	return filepath.Join(p.Root, ref)
 }
 
+var knownAssetRepoNames = []string{"sow-assets", "nwn-assets", "assets"}
+
+func (p *Project) TopDataAssetsDir() string {
+	assets := strings.TrimSpace(p.Config.TopData.Assets)
+	if assets == "" {
+		return ""
+	}
+	if filepath.IsAbs(assets) {
+		return assets
+	}
+	absPath := filepath.Join(p.Root, assets)
+	if _, err := os.Stat(absPath); err == nil {
+		return absPath
+	}
+	relFromParent := filepath.Join(filepath.Dir(p.Root), assets)
+	if _, err := os.Stat(relFromParent); err == nil {
+		return relFromParent
+	}
+	absRoot := filepath.Clean(p.Root)
+	parentDir := filepath.Dir(absRoot)
+	if parentDir != absRoot {
+		for _, repoName := range knownAssetRepoNames {
+			siblingPath := filepath.Join(parentDir, repoName)
+			if _, err := os.Stat(siblingPath); err == nil {
+				return siblingPath
+			}
+		}
+	}
+	return absPath
+}
+
 func (i Inventory) Report() InventoryReport {
 	return InventoryReport{
 		SourceFiles: len(i.SourceFiles),