Honor saved forced vehicle selection at startup

[Intelli]

Description

A startup process can inherit an older settings broadcast, causing it to ignore the saved forced vehicle selection or keep forcing a selection after the setting is disabled. We now refresh the saved model and force flag before vehicle identification, so startup honors the current selection without waiting for a new broadcast. Real-time settings reads stay unchanged.

Requires #163: its settings copy prevents these startup overrides from changing the cached values used by real-time callers. This branch includes that prerequisite commit pending its integration.

Verification

• Added six regression cases for stale vehicle selections and cache preservation; extended the real-time guard to cover model-name reads.
• All 38 settings-module tests passed (32 existing and six new). The 32 existing cases already pass on Dom with Keep startup overrides out of cached settings #163 applied; three new cases fail without this fix.
• Native host prerequisites and Python compilation passed; no new Ruff findings; git diff --check passed.
• Forced vehicle-selection startup changes device-tested on EV9.