[autonomouswork-agent]

Summary

Adds a browser-installable Decky prerelease that starts Expedition 33 directly in GeForce NOW from its normal Steam library page with one tap. The plugin keeps one reusable hidden runner and fails closed when Steam cannot prove its identity or state.

This PR is the complete single-title prerelease. Target-device proof is the next gate: alpha.1 through alpha.4 are preserved as no-go builds, alpha.5 remains an UNVALIDATED DEVICE BUILD, and stable promotion or more supported games must wait for the Lenovo Legion Go S checklist.

Design decisions

Decision	Result
Exact title routing	Only Steam AppID 1903340 can reach the fixed, no-shell GeForce NOW route.
Constant shortcut footprint	One hidden runner stays reusable; the target AppID is supplied only for each launch.
Ownership before mutation	Display name, executable, start directory, empty options, hidden state, and Steam identities must all match before launch or cleanup.
One-tap navigation	Steam's automatic detour to the launched hidden runner is returned exactly once only when its AppID matches a pending plugin launch.
Honest release identity	Every runtime file, including the production frontend bundle, must be tracked at the exact tag before publication.

Session-settled decisions carried from planning: publish an unvalidated prerelease, require one-tap launch, and keep one shared hidden runner (user-directed); use one shared GeForce NOW controller profile (user-approved).

Validation

• pnpm run verify
• 71 frontend tests, 41 backend tests, and 8 release tests pass.
• TypeScript typecheck, production build, deterministic ZIP packaging, and checksum generation pass.
• The two branch CI checks and the tag CI check pass on commit 61ae5bbe5af314c394c186217367251b9fee75c1.
• The published alpha.5 ZIP was downloaded again, byte-compared with the local publication artifact, checksum-verified, and inspected for the exact tag and commit identity.
• Browser QA is not applicable because the product surface is Steam Gaming Mode, not an HTTP route.
• Lenovo Legion Go S behavior is not claimed beyond the user-reported alpha findings; docs/device-proof.md is the release-specific proof checklist.

Release boundary

The current GitHub prerelease is v0.1.0-alpha.5. It is suitable for device testing, not stable promotion. A device failure requires a new alpha build; published assets are never replaced in place.

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