feat: tighten types — MasterPageBlock JSON tags + *string, BlockNote []map[string]any

- Add JSON struct tags to MasterPageBlock and MasterPageDefinition
- Change MasterPageBlock.HtmlContent from string to *string (nullable)
- Change BlockNote renderer signatures from []any to []map[string]any
- Move type assertions to JSON boundary in blocksFromRaw/inlineContentFromRaw

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

plugin/types.go

@@ -47,20 +47,20 @@ type AIAction struct {
 
 // MasterPageBlock defines a block to add to a master page during provisioning.
 type MasterPageBlock struct {
-	BlockKey    string
-	Title       string
-	Content     map[string]any
-	HtmlContent string
-	Slot        string
-	SortOrder   int32
+	BlockKey    string         `json:"block_key"`
+	Title       string         `json:"title"`
+	Content     map[string]any `json:"content"`
+	HtmlContent *string        `json:"html_content"`
+	Slot        string         `json:"slot"`
+	SortOrder   int32          `json:"sort_order"`
 }
 
 // MasterPageDefinition defines a default master page that a plugin provisions.
 type MasterPageDefinition struct {
-	Key           string
-	Title         string
-	PageTemplates []string
-	Blocks        []MasterPageBlock
+	Key           string            `json:"key"`
+	Title         string            `json:"title"`
+	PageTemplates []string          `json:"page_templates"`
+	Blocks        []MasterPageBlock `json:"blocks"`
 }
 
 // Plugin status constants.

render/blocknote.go

@@ -16,7 +16,7 @@ func BlockNoteToHTML(doc map[string]any) string {
 	return renderBlocks(blocks)
 }
 
-func renderBlocks(blocks []any) string {
+func renderBlocks(blocks []map[string]any) string {
 	var sb strings.Builder
 	var currentListType string
 	var listItems []map[string]any
@@ -47,11 +47,7 @@ func renderBlocks(blocks []any) string {
 		currentListType = ""
 	}
 
-	for _, block := range blocks {
-		blockMap, ok := block.(map[string]any)
-		if !ok {
-			continue
-		}
+	for _, blockMap := range blocks {
 		blockType, _ := blockMap["type"].(string)
 
 		if blockType == "bulletListItem" || blockType == "numberedListItem" {
@@ -71,36 +67,40 @@ func renderBlocks(blocks []any) string {
 	return sb.String()
 }
 
-func inlineContentFromRaw(raw any) []any {
+func inlineContentFromRaw(raw any) []map[string]any {
 	switch v := raw.(type) {
 	case []any:
-		return v
-	case []map[string]any:
-		items := make([]any, 0, len(v))
+		items := make([]map[string]any, 0, len(v))
 		for _, item := range v {
-			items = append(items, item)
+			if m, ok := item.(map[string]any); ok {
+				items = append(items, m)
+			}
 		}
 		return items
+	case []map[string]any:
+		return v
 	case string:
 		if v == "" {
 			return nil
 		}
-		return []any{map[string]any{"type": "text", "text": v}}
+		return []map[string]any{{"type": "text", "text": v}}
 	default:
 		return nil
 	}
 }
 
-func blocksFromRaw(raw any) []any {
+func blocksFromRaw(raw any) []map[string]any {
 	switch v := raw.(type) {
 	case []any:
-		return v
-	case []map[string]any:
-		items := make([]any, 0, len(v))
+		items := make([]map[string]any, 0, len(v))
 		for _, item := range v {
-			items = append(items, item)
+			if m, ok := item.(map[string]any); ok {
+				items = append(items, m)
+			}
 		}
 		return items
+	case []map[string]any:
+		return v
 	default:
 		return nil
 	}
@@ -265,14 +265,9 @@ func renderChildren(children any) string {
 	return renderBlocks(blocks)
 }
 
-func renderInlineContent(content []any) string {
+func renderInlineContent(content []map[string]any) string {
 	var sb strings.Builder
-	for _, item := range content {
-		itemMap, ok := item.(map[string]any)
-		if !ok {
-			continue
-		}
-
+	for _, itemMap := range content {
 		itemType, _ := itemMap["type"].(string)
 		text, _ := itemMap["text"].(string)
 		styles, _ := itemMap["styles"].(map[string]any)