* add enroll-to fields to AddIdentity payload
* add AddIdentityViewModel for external JWT signer discovery draft
* wire signer discovery into add-by-URL preflight, simplify JWT signer fetching significantly
* add signer discovery and picker to add-by-URL draft
* clean up enroll identifier payload lambdas to be more readable
* extract dialog fade-in/fade-out animation helpers
* discover external JWT signers and add a dedicated enroll-mode dialog when applicable
* Trigger external auth for enroll to token/cert on 'join network'
* clear the identities list when the tunneler shuts off
* remove identity clear from LoadStatusFromService in favor of the one in ServiceClient_OnClientDisconnected
* initial multi-tun support commit. used for development
* fix reconnect loop
* Update release notes
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Co-authored-by: dovholuknf <46322585+dovholuknf@users.noreply.github.com>