Add realistic ten-IED synthetic demo workspace

[masarray]

Summary

Adds a built-in, clearly labeled synthetic substation demo that can be opened with Ctrl+Shift+D.

Demo content

• 10 realistic IEC 61850 devices: two BCUs, two OCR/GFR relays, line differential, distance, transformer differential, busbar differential, capacitor-bank protection, and bus coupler
• realistic LD/LN/DO/DA summaries, endpoints, operational DataSets, BRCB/URCB acquisition labels, IEC references, FC/type/unit metadata, quality, and IED timestamps
• animated Live Monitor measurements and report pulses
• seeded and continuously generated Sequence of Events rows
• six read-only synthetic GOOSE publishers with APPID, MAC, VLAN/PCP, goCBRef, DataSet, stNum/sqNum, TAL, ordered named leaves, timeline changes, and a recovered supervision warning
• realistic diagnostic journal

Safety and UX

• demo mode is visibly labeled and never opens an MMS or Ethernet transport
• entry is blocked while a real IED session or GOOSE capture is active
• synthetic IED action/control/edit buttons are disabled
• pressing Ctrl+Shift+D again exits and clears the demo workspace

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Keep demo GOOSE state separate from live capture controls

In demo mode, if a user clicks GOOSE Stop and then Start, this reuses the real IsGooseCapturing flag even though _gooseSubscriberRuntime.StartAsync was never called for the synthetic data. StopGooseSubscriberAsync sets the flag back to false, which enables Start; StartGooseSubscriber_Click then uses the demo adapter's Selector (Index = 1) and can start an actual Npcap capture on adapter 1 while demo mode is still active. Use a demo-only capture state or make the GOOSE start/stop commands ignore demo mode.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Block live workspace actions while demo is running

While the demo timer is running, the always-visible Add IED/Open SCL/Open Project controls remain enabled, and Add IED reaches AddOrDiscoverEndpointAsync → ConnectAndConfigureDeviceAsync → _runtime.ConnectAndDiscoverAsync. That lets a user start real MMS sessions inside the advertised read-only demo; subsequent demo ticks still mutate events/status from the old synthetic state, and exiting demo clears Devices without stopping any runtime session added during demo. Guard workspace-mutating actions with IsDemoMode or force demo deactivation before they run.

Useful? React with 👍 / 👎.