fix(dgw,agent): backwards-compatibility for update manifest V1

[Vladyslav Nikonov (vnikonov-devolutions)]

Fixes issue with invalid parsing/serialziation of UpdateManifest V1 (update.json).

Initial PR introduced bug where we expected "Version" field for product instead of "TargetVersion". This PR fixes this invalid behavior. (Also, "Version" is still will be accepted on agent side as field alias, so gateway v2026.2.1 will work correctly with newer agent

[github-actions]

Let maintainers know that an action is required on their side

• Add the label release-required Please cut a new release (Devolutions Gateway, Devolutions Agent, Jetsocat, PowerShell module) when you request a maintainer to cut a new release (Devolutions Gateway, Devolutions Agent, Jetsocat, PowerShell module)

• Add the label release-blocker Follow-up is required before cutting a new release if a follow-up is required before cutting a new release

• Add the label publish-required Please publish libraries (`Devolutions.Gateway.Utils`, OpenAPI clients, etc) when you request a maintainer to publish libraries (Devolutions.Gateway.Utils, OpenAPI clients, etc.)

• Add the label publish-blocker Follow-up is required before publishing libraries if a follow-up is required before publishing libraries

[Benoît Cortier (CBenoit)]

Thank you!

[Copilot]

Pull request overview

This PR fixes backward compatibility for legacy UpdateManifest V1 (update.json) by correcting the expected V1 field name from the incorrectly used "Version" to the canonical "TargetVersion", while still accepting "Version" as an alias to remain compatible with already released gateway/agent builds.

Changes:

• Introduces a dedicated ProductUpdateInfoV1 type that deserializes "TargetVersion" and accepts "Version" as an alias, while serializing back to "TargetVersion".
• Updates V1→V2 normalization/upgrade paths in both Gateway and Agent to convert V1 product payloads into the V2 ProductUpdateInfo.
• Updates and extends unit tests for V1 parsing (including alias acceptance).

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
devolutions-gateway/src/api/update.rs	Converts legacy V1 product entries to V2 ProductUpdateInfo via into() during in-memory upgrade.
devolutions-agent/src/updater/mod.rs	Converts legacy V1 product entries to V2 ProductUpdateInfo via into() during in-memory upgrade.
crates/devolutions-agent-shared/src/update_manifest.rs	Splits V1 vs V2 product payload schemas (TargetVersion vs Version), adds aliasing, and updates tests/docs accordingly.
crates/devolutions-agent-shared/src/lib.rs	Re-exports ProductUpdateInfoV1 from the shared crate API.

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