feat: Add Milestone 3 documentation including feature testing plan, demo notes, and demo flow details

- Introduced comprehensive testing plan for Milestone 3 in m3-client-note.md
- Documented feedback and suggestions from demo sessions in m3-notes.md
- Created detailed demo flow for Milestone 3 in m3.md, outlining user interactions and expected outcomes
- Added planning tasks for Milestone 4 in m4-planning.md, covering backend and frontend development tasks, research, and business tasks

docs/DATACONNECT_GUIDES/DIAGRAMS/uml/team_uml_diagram.mmd

@@ -0,0 +1,79 @@
+---
+config:
+  layout: elk
+  theme: mc
+---
+classDiagram
+    class User {
+        id: String
+        email: String
+        fullName: String
+    }
+
+    class TeamMember {
+        id: UUID
+        teamId: UUID
+        userId: String
+        teamHubId: UUID
+        role: TeamMemberRole
+        inviteStatus: TeamMemberInviteStatus
+        inviteCode: UUID
+    }
+
+    class Team {
+        id: UUID
+        teamName: String
+        ownerId: String
+    }
+
+    class TeamHub {
+        id: UUID
+        teamId: UUID
+        hubName: String
+    }
+
+    class TeamHudDepartment {
+        id: UUID
+        name: String
+        teamHubId: UUID
+    }
+
+    class MemberTask {
+        teamMemberId: UUID
+        taskId: UUID
+    }
+
+    class Task {
+        id: UUID
+        taskName: String
+        status: TaskStatus
+        priority: TaskPriority
+        ownerId: UUID
+    }
+
+    class Vendor {
+        id: UUID
+        companyName: String
+    }
+
+    class Business {
+        id: UUID
+        businessName: String
+    }
+
+    User "1" -- "1" TeamMember : has
+    
+    Team "1" -- "*" TeamHub : contains
+    Team "1" --o "1" Vendor : (ownerId)
+    Team "1" --o "1" Business : (ownerId)
+
+    TeamHub "1" -- "*" TeamHudDepartment : has
+    TeamHub "1" -- "*" TeamMember : is assigned to
+
+    TeamMember "*" -- "1" Team
+    TeamMember "1" -- "*" MemberTask : has assigned
+
+    Task "1" -- "*" MemberTask : is assigned to
+    Task --o Vendor : (ownerId)
+    Task --o Business : (ownerId)
+