P3: integrate trusted-SCL initial snapshot into IED Connection workspace #87

Goal

Make the production IED Connection workspace consume the P2 trusted-SCL runtime instead of leaving MmsSclAssistedConnectClient as an unused core API.

Product behavior

With a trusted CID/SCL loaded

Open CID/SCL → Connect must:

1. Use the bounded SCL parser result as the authoritative model source.
2. Establish the existing proven MMS association.
3. Run MmsTcpLiveDiscoverySession::synchronize_scl().
4. Validate Domains only; do not repeat full NamedVariable/GVAA/DataSet discovery.
5. Build the UI data-model tree from trusted SCL structure/type metadata.
6. Apply P2 initial FC-root snapshot values to the exact SCL leaves.
7. Preserve missing/extra-domain diagnostics without rewriting SCL identity.
8. Keep the association active for subsequent Read/Write/report workflows.
9. Surface the model source clearly in UI/diagnostics.

Without a trusted CID/SCL loaded

Preserve the existing full live-discovery path unchanged as the fallback.

Fail-closed rule

If the user selected a trusted SCL source and parsing/synchronization fails, surface the failure. Do not silently switch to full discovery and thereby change model semantics.

Implementation started on PR #82

• 0b50e9a075fdd95fe7b383d4e7fba04cc9149ec0 — adds MmsSclClientProjection.hpp to project trusted SCL + snapshot evidence into the existing MmsLiveModelDocument/tree shape and collect initial leaf values.
• 79db771f51d10d28b2bc7ad699a86e3b11e00a8b — adds trusted-SCL/model-source state to MmsClientController.
• b95f078e13aa8207614c37695edefa495228f035 — switches MmsClientController::connectToIed() between trusted-SCL synchronization and legacy full discovery, with no silent fallback on trusted-SCL failure.
• b2f42bb3f2851e37232b4d79fd2259460ea839e6 — arms the client trusted-SCL path only after SclWorkspaceController reports a successfully loaded engineering file.

Required QA

• Qt build with strict warnings.
• Existing no-SCL MMS client QA remains green (fallback regression).
• Add trusted-SCL controller QA proving:
  • no GVAA/full discovery on trusted path;
  • SCL LD/LN/DO/DA counts are projected;
  • initial FC-root values land on the correct leaf keys;
  • association remains active;
  • trusted-SCL parse/sync failure does not silently fall back;
  • stale-session/reconnect generation protection remains intact.
• Windows Release Hardening from exact final P3 head.
• External target-client validation remains a separate field gate; do not claim vendor external IEC 61850 client parity solely from internal CI.

Keep this issue OPEN until product integration QA and exact-head package validation pass.