BOLT-1322 [6/7] adapters/oem/tesla: sync internal endpoint POST /internal/tesla/vehicle/check-pairing-status

New internal HTTP endpoint on the oem adapter that synchronously calls fleet_status, derives keyPaired + extendedCapabilities, returns within a single HTTP round-trip. No Kafka, no command.executed event published from this path. Location: adapters/oem/src/routes/ (find the existing internal http surface — likely an Express/Fastify app exposing /internal/* endpoints already; mirror that pattern). Endpoint contract: POST /internal/manufacturers/tesla/vehicle/check-pairing-status Body: { manufacturerDeviceId: string (VIN), manufacturerUserId: string } 200 Response: { keyPaired: boolean | null, extendedCapabilities?: Record<string, unknown> } 4xx: validation errors 5xx: tesla fleet_status unavailable / timed out (caller falls back to cached value) Implementation: 1. Resolve the active Tesla connection for manufacturerUserId via connectionService.getLatestConnection (existing helper, see adapters/oem/src/manufacturers/tesla/events/command.issued/index.ts for the call site reference). 2. Call existing teslaService.getDevices(accessToken) — this is the same call used in publishDeviceStateUpdate; reuse it directly. From its response, extract keyPairedVins (Set) + vehicle_info for the VIN. 3. Call deriveKeyPaired(vin, keyPairedVins, vehicleInfo, undefined) — existing helper. 4. Call extractExtendedCapabilities(vin, vehicleInfo) — existing helper. 5. Return { keyPaired, extendedCapabilities }. 6. Wrap in standard adapter error handling (TeslaApiException → 502 with upstream error details; timeout → 504). Timeout: set a hard 5s deadline on the fleet_status call so we never make Amazon wait forever. Tests: - Happy path: VIN in keyPairedVins set → keyPaired=true returned - VIN not in set → keyPaired=false returned - vehicle_command_protocol_required=false → keyPaired=null returned (per existing deriveKeyPaired semantics) - Tesla API returns 5xx → endpoint returns 502 - Tesla API times out → endpoint returns 504 Branch: havoc/bolt-1322-tesla-sync-endpoint Worktree: ../mono-bolt-1322-tesla-sync-endpoint Depends on: nothing structurally (uses existing helpers) Done when: endpoint test passes, branch builds, integrates cleanly into adapter http surface.