feat(agent): add window recording support via now proto dvc

[pacmancoder]

Adds window recording support to the Devolutions Agent. The implementation uses Windows event hooks to receive foreground window change notifications and optional polling to detect title changes within the same window.

Issue: ARC-353

[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

[Copilot]

Pull request overview

This PR adds window recording support to the devolutions-session agent by implementing a window monitoring system that tracks active window changes on Windows systems. The implementation uses Windows Event Hooks to receive foreground window change notifications and optional polling to detect title changes within the same window.

Key Changes

• Added a new window_monitor module that uses Windows Event Hooks (SetWinEventHook) to monitor foreground window changes
• Integrated window recording capabilities into the DVC task processing system with start/stop message handlers
• Updated the dependency on now-proto-pdu to use a Git branch for new window recording protocol messages

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
devolutions-session/src/dvc/window_monitor.rs	New module implementing window monitoring using Windows Event Hooks and optional polling for title changes, with async event handling through channels
devolutions-session/src/dvc/task.rs	Added window recording start/stop handlers, updated capabilities to include WINDOW_RECORDING flag, and integrated window recording events into the message processing loop
devolutions-session/src/dvc/process.rs	Extended ServerChannelEvent enum with WindowRecordingEvent variant for propagating window change events
devolutions-session/src/dvc/mod.rs	Added window_monitor module declaration
devolutions-session/Cargo.toml	Updated now-proto-pdu dependency to use Git branch and added Win32_UI_Accessibility feature for Windows API
Cargo.lock	Updated now-proto-pdu source to Git repository

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[pacmancoder]

@copilot open a new pull request to apply changes based on the comments in this thread

[Copilot]

@pacmancoder I've opened a new pull request, #1600, to work on those changes. Once the pull request is ready, I'll request review from you.

[pacmancoder]

Testing

• Install devolutions-agent to target machine
• Build and copy devolutions-session.exe to target machine (%PROGRAMFILES%/Devolutions/Agent/DevolutionsSession.exe)
• Use IronRDP to connect to the target machine with DVC proxying via named pipe:
  • cargo run -p ironrdp-client -- -u <LOGIN> -p <PASSWORD> --dvc-proxy Devolutions::Now::Agent=now-proto-GLOBAL <IP>
• Within a few seconds from launching IronRDP launch now proto dvc test CLI:
  • cd <now-proto repo>\dotnet\Devolutions.NowClient.Cli
  • dotnet run --pipe=now-proto-GLOBAL
• When now proto cli opens, execute winrec-start command and observe the received messages

[18:10:02] ACTIVE WINDOW: Program Manager
             Process ID: 7564
             Executable: C:\Windows\explorer.exe
[18:10:02] ACTIVE WINDOW:
             Process ID: 8060
             Executable: C:\Program Files\Mozilla Firefox\firefox.exe
[18:10:03] ACTIVE WINDOW: Mozilla Firefox
             Process ID: 8060
             Executable: C:\Program Files\Mozilla Firefox\firefox.exe
[18:10:04] TITLE CHANGED: What’s new with Firefox 144 — Mozilla Firefox
[18:10:19] TITLE CHANGED: New Tab — Mozilla Firefox