Add UI input for dummy_id_tag in OCPP settings

[snoerenberg]

Description

This feature adds the ability to configure a default/dummy RFID card ID in the OCPP settings. When configured, this ID-Tag will be used for all OCPP transactions (StartTransaction and StopTransaction) regardless of whether a physical RFID card was scanned.

Use Case

This is useful when:

• You don't want to scan an RFID card for every charging session
• Your OCPP backend requires an ID-Tag but you don't have physical RFID cards
• You want to use a fixed ID-Tag for all transactions from this chargepoint

Changes

Backend (core):

• Added dummy_id_tag field to Ocpp dataclass
• Modified chargepoint logic to use dummy_id_tag (if configured) as the first priority for both start_transaction and stop_transaction calls

Frontend (openwb-ui-settings):

• Added "Standard ID-Tag" input field in OCPP settings section
• Includes help text explaining the feature

Behavior

dummy_id_tag	Result
Set	Always use this value for OCPP transactions
Empty	Fall back to scanned RFID tag or vehicle ID (existing behavior)

Configuration

The setting is available under: Einstellungen → Allgemein → Laden → OCPP → Standard ID-Tag

[snoerenberg]

Core: openWB/core#3077