Implemented Vault V4

[d2dyno1]

Tasklist

• Bootstrap Key + Software Entropy to protect against Quantum
• Second-stage credential complementation (depends on Enable credential complementation #124)
• File name shortening (depends on Implemented file name shortening #129)
• Switch to Secomba Base4K
• FormC normalize Base4K names
• Detect corrupted normalization for Base4K names in vault health
• Detect App Platform, and mark as unsupported for now to avoid vault version bumps when it's ready
• V3 to V4 migrators

[Copilot]

Pull request overview

This PR updates the vault format implementation to “Vault V4”, including switching core routines/validators to V4 configuration + keystore models and extending credential-modification flows to optionally use both old and new passkeys (to preserve entropy when available).

Changes:

• Switched core create/unlock/recover/modify-credentials routines to V4 keystore/config models and V4 MAC/keystore derivation paths.
• Extended credential modification API/service pipeline to support “old + new passkey” rotation.
• Bumped LATEST_VERSION to V4 and updated version/config validator logic accordingly.

Reviewed changes

Copilot reviewed 18 out of 18 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
src/Sdk/SecureFolderFS.Sdk/ViewModels/Views/Overlays/CredentialsOverlayViewModel.cs	Splits login vs register key sequences; wires OldPasskey into selection/confirmation flows.
src/Sdk/SecureFolderFS.Sdk/ViewModels/Views/Credentials/CredentialsSelectionViewModel.cs	Threads OldPasskey through to confirmation view model.
src/Sdk/SecureFolderFS.Sdk/ViewModels/Views/Credentials/CredentialsConfirmationViewModel.cs	Uses old+new passkey rotation when OldPasskey is provided; adjusts removal flow.
src/Sdk/SecureFolderFS.Sdk/Services/IVaultManagerService.cs	Adds overload to modify authentication using both old and new passkeys.
src/Platforms/SecureFolderFS.UI/ServiceImplementation/VaultManagerService.cs	Implements the new ModifyAuthenticationAsync overload and forwards to ModifyCredentials routine.
src/Core/SecureFolderFS.Core/VaultAccess/VaultParser.cs	Updates/clarifies V4 entropy-preserving rotation documentation.
src/Core/SecureFolderFS.Core/Validators/VersionValidator.cs	Treats V3 as unsupported when V4 is latest.
src/Core/SecureFolderFS.Core/Validators/ConfigurationValidator.cs	Converts validator to V4 config-only MAC verification.
src/Core/SecureFolderFS.Core/Routines/Operational/UnlockRoutine.cs	Removes V3/V4 branching; unlock now reads/derives V4 only.
src/Core/SecureFolderFS.Core/Routines/Operational/RecoverRoutine.cs	Removes V3/V4 branching; recover now reads/validates V4 only.
src/Core/SecureFolderFS.Core/Routines/Operational/ModifyCredentialsRoutine.cs	Implements V4-only credential rotation, including preserve-entropy rotation when old passkey is available.
src/Core/SecureFolderFS.Core/Routines/Operational/CreationRoutine.cs	Creates V4 keystore/config only.
src/Core/SecureFolderFS.Core/Routines/IModifyCredentialsRoutine.cs	Adds old+new passkey SetCredentials overload to routine interface.
src/Core/SecureFolderFS.Core/Models/SecurityWrapper.cs	Switches wrapper to hold V4 configuration data model.
src/Core/SecureFolderFS.Core/DataModels/VaultConfigurationDataModel.cs	Minor property initialization change (recycle bin size).
src/Core/SecureFolderFS.Core/DataModels/V4VaultKeystoreDataModel.cs	Expands documentation around SoftwareEntropy lifecycle.
src/Core/SecureFolderFS.Core/DataModels/V4VaultConfigurationDataModel.cs	Adds/expands XML docs; removes conversion to legacy config model.
src/Core/SecureFolderFS.Core/Constants.cs	Bumps LATEST_VERSION from V3 to V4.

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[Copilot]

Pull request overview

Copilot reviewed 121 out of 121 changed files in this pull request and generated 12 comments.