Adds a trailing optional `bool LockedInDerived = false` to TemplateAttributeDto,
TemplateAlarmDto and TemplateScriptDto (mirrors the ExecutionTimeoutSeconds
additive precedent — no schemaVersion bump). Populated at export
(ToBundleContent), consumed on import (FromBundleContent, BuildTemplate, and all
three SyncTemplate*Async changed-predicate + copy + new-entity paths, incl. audit
payloads). Old-form bundles that lack the property still deserialize to false.
Claude-Session: https://claude.ai/code/session_01MtdgwpEeCUn6cUA5f1LMPj
Add DataType? ElementDataType to TemplateAttributeDto (optional, default null
for backward-compat with old bundles). Map it in both directions in
EntitySerializer (export + FromBundleContent) and in all three
TemplateAttribute construction sites in BundleImporter (BuildTemplate,
SyncTemplateAttributesAsync add-path, and SyncTemplateAttributesAsync
update-path including change-detection). Two new round-trip tests in
EntitySerializerTests confirm List attributes survive export→import and that
old DTOs with null ElementDataType import cleanly.
Joseph Doherty