Update ECCV 2026 with complete deadline information

Added comprehensive deadline schedule from official ECCV website:
- Paper registration: February 26, 2026
- Paper submission: March 5, 2026 (corrected from March 6)
- Supplemental materials: March 12, 2026
- Reviews released: May 2, 2026
- Rebuttal deadline: May 11, 2026
- Final decisions: June 17, 2026
- Camera ready: June 27, 2026
- Workshop/Tutorial proposals: February 14, 2026

Also added start/end date fields and standardized deadline types.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

src/data/conferences/eccv.yml

@@ -6,20 +6,41 @@
   city: Malmö
   country: Sweden
   date: September 8-13, 2026
+  start: 2026-09-08
+  end: 2026-09-13
   era_rating: a
   tags:
   - computer-vision
   deadlines:
-  - type: submission
+  - type: registration
+    label: Paper Registration
+    date: '2026-02-26 23:59:59'
+    timezone: CET
+  - type: paper
     label: Paper Submission
-    date: '2026-03-06 12:00:00'
-    timezone: UTC+1
+    date: '2026-03-05 23:59:59'
+    timezone: CET
+  - type: supplementary
+    label: Supplemental Materials
+    date: '2026-03-12 23:59:59'
+    timezone: CET
+  - type: review_release
+    label: Reviews Released to Authors
+    date: '2026-05-02 23:59:59'
+    timezone: CET
+  - type: rebuttal_end
+    label: Rebuttal Deadline
+    date: '2026-05-11 23:59:59'
+    timezone: CET
+  - type: notification
+    label: Final Decisions
+    date: '2026-06-17 23:59:59'
+    timezone: CET
+  - type: camera_ready
+    label: Camera Ready Deadline
+    date: '2026-06-27 23:59:59'
+    timezone: CET
   - type: submission
     label: Workshop/Tutorial Proposal Submission
     date: '2026-02-14 23:59:59'
-    timezone: UTC-12
-  - type: submission
-    label: Call for Tutorials Submission
-    date: '2026-02-15 23:59:59'
-    timezone: UTC-12
-  note: Paper submission deadline on March 6th, 2026 at 12:00 PM CET. Workshop/tutorial proposal deadline on February 14th, 2026 (AOE). Call for tutorials submission deadline on February 15th, 2026 (AOE). Additional deadlines including abstract submission, supplementary materials, review release, rebuttal period, notification, and camera ready will be announced closer to the submission date.
+    timezone: AoE