Add task schedule to synthim.md

Added task schedule with important dates for participation and deadlines.

Author: cmihaigabriel

_editions/2026/tasks/synthim.md

@@ -152,6 +152,15 @@ The Media Analysis, Verification, and Retrieval group (MeVer) focuses on social
 IDLab-MEDIA, part of Ghent University and imec, focuses on the representation, processing, compression, interactive delivery and forensics of visual media.
 The Video & Image Sense (VIS) Lab combines artificial and human intelligence to understand video and images. Based at the University of Amsterdam's Informatics Institute, the lab specializes in computer vision, deep learning, and cognitive science research.
 
+
+##### Task Schedule:
+* Registration for task participation opens: January 2026
+* Test data release: 1 March 2026
+* Runs due: 15 May 2026
+* Working notes papers due: 10 June 2026
+* MediaEval 2026 Workshop, Mon.-Tue. 15-16 June 2026, Amsterdam, Netherlands and Online, co-located with ACM ICMR 2026
+* Camera ready deadline: 30 June 2026
+
 #### Acknowledgements
 
 The task organization is supported by the Horizon Europe AI-CODE project that focuses on the development of AI tools for supporting media professionals in their verification and fact-checking activities.