feat(v3): migrate workspace to API, Tauri desktop, and v3 crates; remove legacy MCP stack

- Add apps/api, desktop Tauri shell, domain/application/crypto/device-auth/infrastructure-db
- Replace desktop-daemon vault integration; drop secrets-core and secrets-mcp*
- Ignore apps/desktop/dist and generated Tauri icons; document icon/dist steps in AGENTS.md
- Apply rustfmt; fix clippy (collapsible_if, HTTP method as str)

crates/domain/src/cipher.rs

@@ -0,0 +1,138 @@
+use chrono::{DateTime, Utc};
+use serde::{Deserialize, Serialize};
+use serde_json::Value;
+use uuid::Uuid;
+
+#[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "snake_case")]
+pub enum CipherType {
+    Login,
+    ApiKey,
+    SecureNote,
+    SshKey,
+    Identity,
+    Card,
+}
+
+impl CipherType {
+    pub fn as_str(&self) -> &'static str {
+        match self {
+            Self::Login => "login",
+            Self::ApiKey => "api_key",
+            Self::SecureNote => "secure_note",
+            Self::SshKey => "ssh_key",
+            Self::Identity => "identity",
+            Self::Card => "card",
+        }
+    }
+
+    pub fn parse(input: &str) -> Self {
+        match input {
+            "login" => Self::Login,
+            "api_key" => Self::ApiKey,
+            "secure_note" => Self::SecureNote,
+            "ssh_key" => Self::SshKey,
+            "identity" => Self::Identity,
+            "card" => Self::Card,
+            _ => Self::SecureNote,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+pub struct CustomField {
+    pub name: String,
+    pub value: Value,
+    #[serde(default)]
+    pub sensitive: bool,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Default)]
+pub struct LoginPayload {
+    #[serde(default)]
+    pub username: Option<String>,
+    #[serde(default)]
+    pub uris: Vec<String>,
+    #[serde(default)]
+    pub password: Option<String>,
+    #[serde(default)]
+    pub totp: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Default)]
+pub struct ApiKeyPayload {
+    #[serde(default)]
+    pub client_id: Option<String>,
+    #[serde(default)]
+    pub secret: Option<String>,
+    #[serde(default)]
+    pub base_url: Option<String>,
+    #[serde(default)]
+    pub host: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Default)]
+pub struct SecureNotePayload {
+    #[serde(default)]
+    pub text: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, Default)]
+pub struct SshKeyPayload {
+    #[serde(default)]
+    pub username: Option<String>,
+    #[serde(default)]
+    pub host: Option<String>,
+    #[serde(default)]
+    pub port: Option<u16>,
+    #[serde(default)]
+    pub private_key: Option<String>,
+    #[serde(default)]
+    pub passphrase: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+#[serde(tag = "kind", rename_all = "snake_case")]
+pub enum ItemPayload {
+    Login(LoginPayload),
+    ApiKey(ApiKeyPayload),
+    SecureNote(SecureNotePayload),
+    SshKey(SshKeyPayload),
+}
+
+impl Default for ItemPayload {
+    fn default() -> Self {
+        Self::SecureNote(SecureNotePayload::default())
+    }
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+pub struct CipherView {
+    pub id: Uuid,
+    pub cipher_type: CipherType,
+    pub name: String,
+    pub folder: String,
+    #[serde(default)]
+    pub notes: Option<String>,
+    #[serde(default)]
+    pub custom_fields: Vec<CustomField>,
+    #[serde(default)]
+    pub deleted_at: Option<DateTime<Utc>>,
+    pub revision_date: DateTime<Utc>,
+    pub payload: ItemPayload,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+pub struct Cipher {
+    pub id: Uuid,
+    pub user_id: Uuid,
+    pub object_kind: String,
+    pub cipher_type: CipherType,
+    pub revision: i64,
+    pub cipher_version: i32,
+    pub ciphertext: Vec<u8>,
+    pub content_hash: String,
+    pub deleted_at: Option<DateTime<Utc>>,
+    pub created_at: DateTime<Utc>,
+    pub updated_at: DateTime<Utc>,
+}