Add missing E2E test coverage

[noraeb]

Following the integration test coverage review, we identified several user flows in CoMPAS that currently have no E2E test coverage in compas-deployment/integration-testing.

Covered

Area	Flow	Happy path	Negative path	Suite
Open	Open project from local file	✅	—	TestSuite001
Open	Open local file + add to CoMPAS (REST)	✅	—	TestSuite001
Open	Open local file + add to CoMPAS (WebSocket)	✅	—	TestSuite001
Open	Open project from CoMPAS (REST)	✅	—	TestSuite001
Open	Open project from CoMPAS (WebSocket)	✅	—	TestSuite001
Save	Open from CoMPAS (REST) → save to local file	✅	—	TestSuite001
Save	Save existing project as new project	✅	—	TestSuite001
Save	Save local project as new version of existing project	✅	—	TestSuite001
Save	Save to CoMPAS (REST) with invalid name	—	✅	TestSuite001
Save	Save to CoMPAS (WebSocket) with invalid name	—	✅	TestSuite001
Versions	Versions tab shows zero versions	✅	—	TestSuite002
Versions	Versions tab shows one version	✅	—	TestSuite002
Versions	Every save creates a new version	✅	—	TestSuite002
Versions	Add a new version from a local file	✅	—	TestSuite002
Versions	Restore first version from list	✅	—	TestSuite002
Versions	Delete first version from list	✅	—	TestSuite002
Versions	Delete all versions	✅	—	TestSuite002
Versions	Compare current version vs. CoMPAS version	✅	—	TestSuite002
Versions	Compare current version, wrong selection count	—	✅	TestSuite002
Versions	Compare two versions from CoMPAS	✅	—	TestSuite002
Versions	Compare versions, wrong selection count	—	✅	TestSuite002
CIM Mapping	Create project from CIM file	✅	—	TestSuite003
CIM Mapping	Create project from invalid CIM filename	—	✅	TestSuite003
Auto-Alignment	Execute for single substation	✅	—	TestSuite004
Auto-Alignment	Execute for multiple substations	✅	—	TestSuite004
Auto-Alignment	Incomplete configuration	—	✅	TestSuite004
Validation	SCL validator (WebSocket) — OCL errors	⚠️ (only failure asserted)	✅	TestSuite005
Validation	SCL validator (REST) — OCL errors	⚠️ (only failure asserted)	✅	TestSuite005
Validation	SCL validator (WebSocket) — XSD errors	⚠️ (only failure asserted)	✅	TestSuite005
Validation	SCL validator (REST) — XSD errors	⚠️ (only failure asserted)	✅	TestSuite005

Gaps

Area	Feature	Frontend source	Why it matters
Merge	Merge two SCL documents	src/menu/CompasMerge.ts	Data-destructive operation on production configs; no safety net at all
Session	Session expiring mid-edit (warning dialog)	src/compas/CompasSessionExpiringDialog.ts	Long editing sessions are normal for this tool; silent failure risks lost work
Session	Session expired (forced logout)	src/compas/CompasSessionExpiredDialog.ts	Same as above
Backend resilience	Save when SCL Data Service is unreachable/errors (5xx, timeout)	n/a (only client-side validation tested)	Realistic failure mode in any deployed environment; only "bad filename" is tested today
Backend resilience	Open when SCL Data Service is unreachable/errors	n/a	Same as above, on read path
Import	Import IEDs	src/menu/CompasImportIEDs.ts	Relatively complex feature, that is currently untested
Import	Import from external API	src/menu/CompasImportFromApi.ts, src/compas/CompasImportFromApi.ts	Check: is this feature used by anyone?
Compare	Compare IED	src/menu/CompasCompareIED.ts	Different mechanism from version-compare (already tested); untested
Update	Update Substation	src/menu/CompasUpdateSubstation.ts	No coverage
Validation	Valid file passes validation (explicit happy-path assertion)	n/a	Current tests only assert the failure branch of OCL/XSD checks
Validation	Malformed / not-well-formed XML input	n/a	Different failure class than "schema-valid but semantically wrong"
Auto-Alignment	Malformed alignment input (vs. "incomplete config")	n/a	Different failure class than the one already tested
Auto-Alignment	Alignment run that produces zero changes	n/a	Silent no-op vs. crash are different bugs; unverified
Scale	Open / align / validate a large substation file	n/a	Performance/timeout boundary unverified
SCL types	SCL type list / select	src/compas/CompasSclTypeList.ts, CompasSclTypeSelect.ts	Same as above

Acceptance Criteria

• New test cases added for all missing flows
• Tests run green in CI across configured browsers
• Coverage matrix updated to reflect new "Covered" status