Refactor: Testable Keychain and Identity Manager (#584)

* Make static functions instance functions to be testable

* Injectable KeychainManager + Mock + updated tests

* Remove `pendingActions` from identity manager (dead code)

* Remove `getHandshakeState` from identity manager (dead code)

* Remove `getAllSocialIdentities` from identity manager (dead code)

* Remove `getCryptographicIdentity` from identity manager (dead code)

* Remove `resolveIdentity` from identity manager (dead code)

* Identity Manager: minor clean up

* Put Identity Manager behind a protocol

* Remove Keychain and Identity Manager singletons

* Tests: include MockKeychain/MockIdentityManager in project; init identityManager in CommandProcessorTests

---------

Co-authored-by: jack <jackjackbits@users.noreply.github.com>

bitchatTests/Mocks/MockIdentityManager.swift

@@ -0,0 +1,80 @@
+//
+// MockIdentityManager.swift
+// bitchat
+//
+// This is free and unencumbered software released into the public domain.
+// For more information, see <https://unlicense.org>
+//
+
+import Foundation
+@testable import bitchat
+
+final class MockIdentityManager: SecureIdentityStateManagerProtocol {
+    private let keychain: KeychainManagerProtocol
+    
+    init(_ keychain: KeychainManagerProtocol) {
+        self.keychain = keychain
+    }
+    
+    func loadIdentityCache() {}
+    
+    func saveIdentityCache() {}
+    
+    func forceSave() {}
+    
+    func getSocialIdentity(for fingerprint: String) -> SocialIdentity? {
+        nil
+    }
+    
+    func upsertCryptographicIdentity(fingerprint: String, noisePublicKey: Data, signingPublicKey: Data?, claimedNickname: String?) {}
+    
+    func getCryptoIdentitiesByPeerIDPrefix(_ peerID: String) -> [CryptographicIdentity] {
+        []
+    }
+    
+    func updateSocialIdentity(_ identity: SocialIdentity) {}
+    
+    func getFavorites() -> Set<String> {
+        Set()
+    }
+    
+    func setFavorite(_ fingerprint: String, isFavorite: Bool) {}
+    
+    func isFavorite(fingerprint: String) -> Bool {
+        false
+    }
+    
+    func isBlocked(fingerprint: String) -> Bool {
+        false
+    }
+    
+    func setBlocked(_ fingerprint: String, isBlocked: Bool) {}
+    
+    func isNostrBlocked(pubkeyHexLowercased: String) -> Bool {
+        true
+    }
+    
+    func setNostrBlocked(_ pubkeyHexLowercased: String, isBlocked: Bool) {}
+    
+    func getBlockedNostrPubkeys() -> Set<String> {
+        Set()
+    }
+    
+    func registerEphemeralSession(peerID: String, handshakeState: HandshakeState) {}
+    
+    func updateHandshakeState(peerID: String, state: HandshakeState) {}
+    
+    func clearAllIdentityData() {}
+    
+    func removeEphemeralSession(peerID: String) {}
+    
+    func setVerified(fingerprint: String, verified: Bool) {}
+    
+    func isVerified(fingerprint: String) -> Bool {
+        true
+    }
+    
+    func getVerifiedFingerprints() -> Set<String> {
+        Set()
+    }
+}