fix: remove redundant stateful_streamplot example (#362)

## Summary
- Remove duplicate stateful_streamplot example that was functionally
identical to streamplot_demo
- Both examples used the same 20x20 grid, same circular flow field, same
API calls
- Only difference was title text and directory structure
- Clean up all documentation references, build system entries, and
source file mappings

## Changes Made
- **Deleted**: example/fortran/stateful_streamplot/ directory and all
contents
- **Deleted**: doc/examples/stateful_streamplot.md documentation 
- **Updated**: Documentation index files to remove references
- **Updated**: Makefile to remove output directory creation
- **Updated**: DESIGN.md to remove from example listings
- **Updated**: Source files (fortplot_doc_examples.f90,
fortplot_doc_media.f90) to remove mappings

## Validation
- All references to stateful_streamplot have been completely removed
- streamplot_demo remains as the single comprehensive streamplot example
- Build system updated to match new structure

## Test Plan
- [x] Verify build system works without stateful_streamplot references
- [x] Confirm documentation no longer references removed example
- [x] Ensure streamplot_demo still functions as expected

Fixes #336

Author: krystophny

BACKLOG.md

@@ -12,6 +12,13 @@
 - [x] #330: Fix - Old plot not cleared in second figure (figure() call) in contour_demo.html (COMPLETED)
 - [ ] #336: Fix - Streamplot and stateful streamplot example redundant
 
+**Critical Infrastructure Issues (High Priority)** - ESCALATED TO DOING
+
+**User-Facing Issues (Medium Priority)**
+- [ ] #328: Fix - One legend entry too much in basic_plots.html second plot
+- [ ] #327: Fix - MP4 link not showing on animation.html
+- [ ] #347: Fix - Remove funny header from https://lazy-fortran.github.io/fortplot/
+
 **Infrastructure & Documentation Issues (Lower Priority)**
 - [ ] #323: Test - add edge case tests for PDF heatmap color validation
 - [ ] #324: Refactor - define epsilon constant for numerical comparisons
@@ -24,7 +31,10 @@
 - [ ] #360: Refactor - split fortplot_raster.f90 to comply with file size limits
 
 ## DOING (Current Work)
-- [ ] #336: Fix - Streamplot and stateful streamplot example redundant
+- [ ] #361: Fix - Windows CI: test_legend_comprehensive and test_streamplot runtime failures
+
+## BLOCKED (By Windows CI)
+- [ ] #336: Fix - Streamplot and stateful streamplot example redundant (PR #362 ready but blocked by Windows CI)
 
 ## BLOCKED (Infrastructure Issues)
 

DESIGN.md

@@ -690,7 +690,6 @@ subroutine streamplot(self, x, y, u, v, density, color, linewidth, &
 - scatter_demo - 2D scatter plots
 - show_viewer_demo - Display plot in viewer
 - smart_show_demo - Smart show functionality
-- stateful_streamplot - Streamplot with stateful API
 - streamplot_demo - Vector field visualization
 - unicode_demo - Unicode text support
 

Makefile

@@ -165,7 +165,6 @@ create_build_dirs:
 	@mkdir -p output/example/fortran/show_viewer_demo
 	@mkdir -p output/example/fortran/smart_show_demo
 	@mkdir -p output/example/fortran/animation
-	@mkdir -p output/example/fortran/stateful_streamplot
 	@mkdir -p output/example/fortran/annotation_demo
 	@mkdir -p output/example/fortran/histogram_demo
 	@mkdir -p output/example/fortran/subplot_demo

doc/examples/index.md

@@ -65,8 +65,6 @@ Intelligent display mode selection based on environment.
 ### [Save Animation Demo](./save_animation.html)
 Creating animated plots and saving to video files.
 
-### [Stateful Streamplot](./stateful_streamplot.html)
-Time-evolving vector field animations.
 
 ---
 

doc/examples/stateful_streamplot.md

@@ -45,7 +45,6 @@ Complete working examples with source code and generated plots.
 - [Scatter Demo](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/scatter_demo) - Scatter plot basics
 - [Show Viewer](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/show_viewer_demo) - Interactive display
 - [Smart Show](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/smart_show_demo) - Intelligent display
-- [Stateful Streamplot](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/stateful_streamplot) - Vector field evolution
 - [Streamplot](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/streamplot_demo) - Vector field visualization
 - [Subplot Demo](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/subplot_demo) - Multiple plot grids
 - [Unicode Demo](https://github.com/lazy-fortran/fortplot/tree/main/example/fortran/unicode_demo) - Mathematical symbols

doc/index.md

@@ -34,7 +34,6 @@ make example ARGS="example_name"
 - [colored_contours](./colored_contours/) - Filled contours with colormaps
 - [pcolormesh_demo](./pcolormesh_demo/) - Pseudocolor mesh plots
 - [streamplot_demo](./streamplot_demo/) - Vector field visualization
-- [stateful_streamplot](./stateful_streamplot/) - Time-evolving fields
 
 ### Scaling and Styling
 - [scale_examples](./scale_examples/) - Log and symlog scales

example/fortran/README.md

@@ -36,8 +36,7 @@ pure subroutine get_example_dir(index, dir)
         case(14); dir = "example/fortran/show_viewer_demo"
         case(15); dir = "example/fortran/smart_show_demo"
         case(16); dir = "example/fortran/animation"
-        case(17); dir = "example/fortran/stateful_streamplot"
-        case(18); dir = "example/fortran/annotation_demo"
+        case(17); dir = "example/fortran/annotation_demo"
         case default; dir = ""
         end select
     end subroutine get_example_dir
@@ -63,8 +62,7 @@ pure subroutine get_example_name(index, name)
         case(14); name = "show_viewer_demo"
         case(15); name = "smart_show_demo"
         case(16); name = "animation"
-        case(17); name = "stateful_streamplot"
-        case(18); name = "annotation_demo"
+        case(17); name = "annotation_demo"
         case default; name = ""
         end select
     end subroutine get_example_name