Add first-class Vega OS TV support for Vega Virtual Devices #1400

Motivation

Amazon's Vega OS replaces the legacy Kepler naming/toolchain for current Fire TV development. agent-device needs a first-class, agent-friendly TV path that uses the official Vega CLI and Vega Virtual Device (VVD), preserves the existing session model, and exposes remote controls through the shared TV command surface.

Initial scope

The first increment is deliberately VVD-only until durable physical Fire TV evidence is attached to a follow-up:

• discover running Vega Virtual Devices through the official Vega CLI
• open and close apps by Vega component ID
• support back, home, and the complete shared TV remote matrix
• support Select aliases, the long-press preset, and exact hold durations from 0–10,000 ms
• diagnose missing/misconfigured Vega tooling
• report unsupported capture, selector, install, text/touch/gesture, logs, and performance operations explicitly
• document that AWS Device Farm does not currently expose Vega OS/Fire TV through its Android/iOS device APIs

Physical Vega Fire TV support, screenshot/snapshot/selectors, app inventory, installation, logs, and performance are follow-up surfaces and must not be claimed by this increment.

Dependencies and sequencing

Blocked by: none.

External prerequisites:

• Amazon Vega Developer Tools and an SDK-matched VVD
• a developer component ID available to the local Vega environment

Ordering:

1. Land the VVD-only platform model, provider boundary, lifecycle, and remote controls.
2. Add physical Fire TV admission only after durable PR-accessible evidence covers discovery, lifecycle, every remote button, aliases, and hold boundaries on hardware.
3. Add capture/selector and remaining command families as separate follow-ups because they require new semantic backends rather than extensions to remote input.

Acceptance criteria

• vega is represented in platform, inventory, routing, serialization, command metadata, and typed client contracts without leaking internal aliases.
• Discovery returns running VVDs and excludes unvalidated physical Fire TV devices.
• open, close, back, home, and tv-remote admit Vega VVD targets and reject physical/non-TV Vega targets with an actionable VVD-only hint.
• Up, Down, Left, Right, Select, Menu, Home, and Back map to their expected Vega inputd-cli keys.
• ok, center, and enter normalize to Select.
• Exact holds accept 0–10,000 ms, and the Vega subprocess timeout always includes fixed startup/transport overhead beyond the requested hold duration.
• Unsupported command families fail explicitly rather than silently falling back to ADB or another platform.
• CLI help, README, website documentation, client guidance, security notes, and the versioned agent-device skill state the VVD-only boundary.
• Contract, unit, parity, provider-integration, CLI/help, and SkillGym planning tests cover the supported surface.
• Live VVD evidence covers discovery, lifecycle, the full remote matrix, aliases, exact/long holds, focus movement, and clean session teardown.
• AWS Device Farm support is not claimed unless its public platform/device API adds Vega/Fire TV inventory.

Evidence required for physical-device follow-up

• exact physical Fire TV model and Vega OS version
• durable PR-accessible command transcript and screenshots
• discovery plus explicit serial selection
• app open/close
• all eight remote buttons and Select aliases
• long-press preset and 10,000 ms boundary hold
• final session/device cleanup