feat(P3.T2): DeviceRecord.revokedAt + revokeDevice wrapper

Extend DeviceRecord with revokedAt field, update registerDevice and
listOwnDevices selects to include revoked_at, add revokeDevice RPC
helper, update db-types to reflect T1 migration schema, and add
vitest coverage for all new behaviour.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/db-types/src/index.ts

@@ -119,6 +119,7 @@ export type Database = {
           name: string
           platform: Database["public"]["Enums"]["device_platform"]
           public_key: string | null
+          revoked_at: string | null
           user_id: string
         }
         Insert: {
@@ -128,6 +129,7 @@ export type Database = {
           name: string
           platform: Database["public"]["Enums"]["device_platform"]
           public_key?: string | null
+          revoked_at?: string | null
           user_id: string
         }
         Update: {
@@ -137,6 +139,7 @@ export type Database = {
           name?: string
           platform?: Database["public"]["Enums"]["device_platform"]
           public_key?: string | null
+          revoked_at?: string | null
           user_id?: string
         }
         Relationships: []
@@ -481,6 +484,7 @@ export type Database = {
     Functions: {
       accept_dm: { Args: { conversation_id: string }; Returns: undefined }
       are_friends: { Args: { a: string; b: string }; Returns: boolean }
+      revoke_device: { Args: { p_device_id: string }; Returns: undefined }
       attachment_object_conv_id: {
         Args: { object_name: string }
         Returns: string