Add July 2026 meetup announcement and update challenges for July Scarf Seams challenge

challenges.md

@@ -9,31 +9,31 @@ Welcome to our monthly 3D printing challenges! Each month features a unique them
 
 ## Active Challenge
 
-### June 2026: "Show & Tell Extravaganza!"
+### July 2026: "Scarf Seams"
 
-**Theme**: Show & Tell
+**Theme**: Scarf Seam Placement & Settings
 
 **Key Details**:
 
-- **Model**: Any 3D printed project
-- **Goal**: Share your work with the community
-- **Reward**: Participants enter a drawing for one of 5 free spools of filament!
+- **Model**: Sphere with scarf seam (max 75mm cubed)
+- **Goal**: Master scarf seam placement and settings
+- **Focus**: Share your settings and techniques for clean seams
 
 **[View Full Challenge Details](https://meetup.fargo3d.com/Fargo3d/3DPrintMeetup/wiki/Current-Challenge)**
 
 ## Upcoming Challenge
 
-### July 2026: "[Theme TBD]"
+### August 2026: "[Theme TBD]"
 
 **Status**: Planning in progress
 
 **Expected Timeline**:
 
-- **Announcement**: June meeting (June 2026)
-- **Submission Period**: July 2026
-- **Judging**: July 2026
+- **Announcement**: July meeting (July 2026)
+- **Submission Period**: August 2026
+- **Judging**: August 2026
 
-**[View Challenge Placeholder](./challenges/July-2026/readme.md)**
+**[View Challenge Placeholder](./challenges/August-2026/readme.md)**
 
 ## Challenge Archive
 
@@ -43,8 +43,9 @@ Welcome to our monthly 3D printing challenges! Each month features a unique them
 |-------|---------------|-------|--------|
 | April | "Bring an Experiment" | Try something new | **Archived** |
 | May | "Bring an Experiment (Round 2!)" | Try something new, crazy, or wild | **Archived** |
-| June | "Show & Tell Extravaganza!" | Community Showcase | **Active** |
-| July | [TBD] | [TBD] | Planning |
+| June | "Show & Tell Extravaganza!" | Community Showcase | **Archived** |
+| July | "Scarf Seams" | Seam Placement & Settings | **Active** |
+| August | [TBD] | [TBD] | Planning |
 
 ### 2025 Challenges