feat: add RDP keep-alive to windows-rdp module

[samuel-asleep]

Description

Adds optional keep-alive functionality to automatically extend workspace sessions during active RDP connections. Uses background PowerShell script to monitor port 3389 and reports activity via coder stat connectivity.

Type of Change

• Feature/enhancement

Module Information

Path: registry/coder/modules/windows-rdp
New version: v1.4.0
Breaking change:

• Yes
• No

Changes

Variables:

• keepalive (bool, default: false) - enables RDP connection monitoring
• keepalive_interval (number, default: 300) - check interval in seconds

Implementation:

• Conditional coder_script resource spawns background PowerShell process
• Monitors Get-NetTCPConnection -LocalPort 3389 -State Established
• Invokes coder stat connectivity on active connections to extend deadline
• Uses start_blocks_login = false to avoid delaying workspace startup

Tests:

• Terraform tests verify conditional resource creation
• TypeScript tests validate script generation and interval configuration

Usage

module "windows_rdp" {
  source             = "registry.coder.com/coder/windows-rdp/coder"
  version            = "1.4.0"
  agent_id           = coder_agent.main.id
  keepalive          = true
  keepalive_interval = 300
}

Testing & Validation

• Tests pass (bun test)
• Code formatted (bun fmt)
• Changes tested locally

Issues/claim

• Resolves Windows RDP Keep Alive - Extend workspace sessions during active RDP connections #200
• /claim Windows RDP Keep Alive - Extend workspace sessions during active RDP connections #200

[matifali]

@samuel-asleep, please attach a video demoing this as described in #213

[samuel-asleep]

@matifali OK will do, but In the meantime I'll convert this pr to draft