Improve annotation mode sorting, status updates, and notifications

[anderstorstensson]

Features:

• Sort unclassified images by ROI area (largest first) in annotation mode This groups similar-sized organisms together for faster annotation
• Add width, height columns to classifications data frame for size-based sorting

Bug fixes:

• Fix sample dropdown not updating status symbol (pencil) after saving Use JavaScript to update display text without rebuilding entire dropdown
• Only update sample status when changes are actually saved Previously status changed even when switching from unchanged samples
• Fix incorrect image count in loading notifications Now shows count after filtering empty triggers, not before

Files changed:

• R/sample_loading.R: Add width/height columns to all loading functions
• R/server.R:
  • Add pending_sample_select to reactiveValues
  • Add update_current_sample_status() helper using JavaScript
  • Modify filtered_images() reactive for size-based sorting in annotation mode
  • Capture save_sample_annotations() return value before updating status
  • Move loading notification to after empty trigger filtering
  • Add mode_message parameter to extract_sample_images()

[codecov-commenter]

Codecov Report

❌ Patch coverage is 93.75000% with 2 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
R/sample_loading.R	93.75%	2 Missing ⚠️

@@            Coverage Diff             @@
##             main       #5      +/-   ##
==========================================
+ Coverage   86.89%   87.59%   +0.70%     
==========================================
  Files           4        4              
  Lines         351      379      +28     
==========================================
+ Hits          305      332      +27     
- Misses         46       47       +1     

Files with missing lines	Coverage Δ
R/sample_loading.R	97.40% <93.75%> (-0.56%)	⬇️

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.