Task: Adopt the base in the history-dialog template and roll out

Bring the 61 generated history dialogs onto the target form: the base renders fields and changes straight from the response, and the per-entity dialogs shrink to generated declarations.

Gated on the codegen org-model migration: this task must not force codegen changes while entity models migrate. It proceeds component by component as each component's models settle, or waits for the migration to complete.

• All generated history dialogs derive from the base; no duplicated pipeline remains.
• Interim template method and helpers removed.
• History responses no longer ship full domain payloads.
• Zero-diff regeneration checks green.

1. Update cpp_qt_history_dialog.{hpp,cpp}.mustache and qt_history_dialog_ui.mustache: derive from HistoryDialogBase target form; remove the duplicated pipeline.
2. Per domain: add the entity field mappers and extend the history handlers (mechanical application of the pilot pattern).
3. Regenerate per component; zero-diff guardrails catch drift.
4. Remove the interim calculateDiff machinery from the base once no dialog uses it; drop full domain payloads from history responses once no client reads them.