VITEC headless: ContentElementResolver, Product fields (videofile, showdatapath)

- New Classes/Service/ContentElementResolver.php: parses TYPO3 typolink
  (t3://record?identifier=tt_content&uid=N, t3://page?uid=P#N, plain numeric)
  to a normalised tt_content envelope ({id,type,colPos,sorting,appearance,
  data}), recursively resolving any nested VITEC list-plugin children.
- ProductListJsonRenderer / ProductShowJsonRenderer: contentelement and
  contentelementcta now emit the resolved object instead of the raw
  typolink string (breaking change at those two keys).
- Product model: new field videofile (FAL, single video upload in tab
  Images and Videos, mp4/webm/ogv/mov/m4v); new bool field showdatapath
  (toggle at end of General tab, controls the "Datapath is now Vitec"
  graphic in the frontend). ext_tables.sql, TCA, model property +
  getter/setter, and both renderers updated accordingly.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

packages/vitec/ext_tables.sql

@@ -51,6 +51,8 @@ CREATE TABLE tx_vitec_domain_model_product (
     productlayout int(11) DEFAULT '0' NOT NULL,   
     contentelement varchar(255) DEFAULT '' NOT NULL,
     contentelementcta varchar(255) DEFAULT '' NOT NULL,
+    videofile int(11) unsigned DEFAULT '0' NOT NULL,
+    showdatapath smallint(5) unsigned DEFAULT '0' NOT NULL,
     KEY parent (pid)
 );
 CREATE TABLE tx_vitec_domain_model_download (
@@ -168,4 +170,4 @@ ADD type VARCHAR(255) DEFAULT '' NOT NULL;
 
 CREATE TABLE tt_content (
     tx_vitec_bg_variant VARCHAR(20) DEFAULT 'none' NOT NULL
-);
+);