Update documentation for completed dev13 features

Mark auto-crop, frame rate conversion, and encoder presets as complete in TODO.md.
Add detailed feature descriptions to DONE.md for all three priority features.

DONE.md

@@ -27,6 +27,16 @@ This file tracks completed features, fixes, and milestones.
   - Supports both film (24 fps) and broadcast standards (25/29.97/30)
   - Uses FFmpeg fps filter for frame rate conversion
 
+- ✅ **Encoder Preset Descriptions with Speed/Quality Trade-offs**
+  - Detailed information for all 9 preset options
+  - Speed comparisons relative to "slow" and "medium" baselines
+  - File size impact percentages for each preset
+  - Visual icons indicating speed categories (⚡⏩⚖️🎯🐌)
+  - Recommends "slow" as best quality/size ratio
+  - Dynamic hint updates when preset changes
+  - Helps users make informed encoding time decisions
+  - Ranges from ultrafast (~10x faster, ~30% larger) to veryslow (~5x slower, ~15-20% smaller)
+
 - ✅ **Compare Module**
   - Side-by-side video comparison interface
   - Load two videos and compare detailed metadata

TODO.md

@@ -16,10 +16,10 @@ This file tracks upcoming features, improvements, and known issues.
   - Auto-suggest 60→30fps conversion with size estimate
   - Show file size impact (40-50% reduction for 60→30)
 
-- [ ] **HEVC/H.265 preset options**
-  - Add preset dropdown: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow
+- [x] **HEVC/H.265 encoder preset options** (v0.1.0-dev13 - COMPLETED)
+  - Preset dropdown: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow
   - Show time/quality trade-off estimates
-  - Default to "slow" for best quality/size balance
+  - Recommend "slow" for best quality/size balance
 
 - [ ] **Advanced filters module**
   - Denoising: hqdn3d (fast), nlmeans (slow, high quality)