Add seamless migration path from legacy agents to unified agent:
- Add AgentType field to report payloads (unified vs legacy detection)
- Update server to detect legacy agents by type instead of version
- Add UI banner showing upgrade command when legacy agents are detected
- Add deprecation notice to install-host-agent.ps1
- Create install-docker-agent.sh stub that redirects to unified installer
Legacy agents (pulse-host-agent, pulse-docker-agent) now show a "Legacy"
badge in the UI with a one-click copy command to upgrade to the unified
agent.
Extends Docker container monitoring with comprehensive disk and storage information:
- Writable layer size and root filesystem usage displayed in new Disk column
- Block I/O statistics (read/write bytes totals) shown in container drawer
- Mount metadata including type, source, destination, mode, and driver details
- Configurable via --collect-disk flag (enabled by default, can be disabled for large fleets)
Also fixes config watcher to consistently use production auth config path instead of following PULSE_DATA_DIR when in mock mode.