fix(slack): use empty string fallback for email and make type non-optional

Author: waleedlatif1

apps/sim/tools/slack/get_user.ts

@@ -85,7 +85,7 @@ export const slackGetUserTool: ToolConfig<SlackGetUserParams, SlackGetUserRespon
           first_name: profile.first_name || '',
           last_name: profile.last_name || '',
           title: profile.title || '',
-          email: profile.email ?? null,
+          email: profile.email || '',
           phone: profile.phone || '',
           skype: profile.skype || '',
           is_bot: user.is_bot || false,

apps/sim/tools/slack/list_users.ts

@@ -93,7 +93,7 @@ export const slackListUsersTool: ToolConfig<SlackListUsersParams, SlackListUsers
         name: user.name,
         real_name: user.real_name || user.profile?.real_name || '',
         display_name: user.profile?.display_name || '',
-        email: user.profile?.email ?? null,
+        email: user.profile?.email || '',
         is_bot: user.is_bot || false,
         is_admin: user.is_admin || false,
         is_owner: user.is_owner || false,

apps/sim/tools/slack/types.ts

@@ -963,7 +963,7 @@ export interface SlackUser {
   title?: string
   phone?: string
   skype?: string
-  email?: string | null
+  email: string
   is_bot: boolean
   is_admin: boolean
   is_owner: boolean