feat(platform): add vehicle data management console

vehicle-data-platform/docs/product-spec.md

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+# Vehicle Data Platform Product Spec
+
+## Visual Direction
+
+The UI is a professional vehicle data operations console. It uses Semi UI as the component base, a restrained gray-white control-room palette, dense but readable tables, right-side drawers for detail, and blue-cyan accents for primary actions. It should feel closer to a cloud data console than a marketing dashboard.
+
+## Primary Screens
+
+1. Dashboard: KPI summary, protocol distribution, vehicle map preview, quality issues, and link health.
+2. Vehicles: table-first identity and vehicle registry.
+3. Realtime: table/map switch for current vehicle state.
+4. Vehicle Detail: identity header and tabs for latest state, history, raw, mileage, and quality.
+5. History: location and raw-frame query workspace.
+6. Mileage: daily and range mileage analysis.
+7. Quality: data quality and link health workspace.
+
+## Interaction Rules
+
+- Tables are the default data surface.
+- Filters stay above the table.
+- Details open in a right drawer unless a full route is needed.
+- Error and empty states must be explicit.
+- No decorative hero, no oversized marketing card layout, no dark large-screen style.
+