feat(compiler): convert text mixed with elements into createVNode calls

This ensures they are tracked as dynamic children when inside blocks.
Also guaruntees compiled vnodes always have vnode children in arrays
so that they can skip normalizeVNode safely in optimized mode.

packages/compiler-core/src/ast.ts

@@ -35,6 +35,7 @@ export const enum NodeTypes {
   IF,
   IF_BRANCH,
   FOR,
+  TEXT_CALL,
   // codegen
   JS_CALL_EXPRESSION,
   JS_OBJECT_EXPRESSION,
@@ -86,6 +87,7 @@ export type TemplateChildNode =
   | CommentNode
   | IfNode
   | ForNode
+  | TextCallNode
 
 export interface RootNode extends Node {
   type: NodeTypes.ROOT
@@ -227,6 +229,12 @@ export interface ForNode extends Node {
   codegenNode: ForCodegenNode
 }
 
+export interface TextCallNode extends Node {
+  type: NodeTypes.TEXT_CALL
+  content: TextNode | InterpolationNode | CompoundExpressionNode
+  codegenNode: CallExpression
+}
+
 // We also include a number of JavaScript AST nodes for code generation.
 // The AST is an intentionally minimal subset just to meet the exact needs of
 // Vue render function generation.