Fix @example block references in SDE tutorial documentation

Resolves build failure where plotting commands tried to reference solution variables from different @example blocks.

- Changed `@example sde` to `@example sde2` for Lorenz SDE plot (line 195)
- Changed `@example sde` to `@example sde3` for scalar noise SDE plot (line 235)

This fixes the ArgumentError: "Collection has multiple elements, must contain exactly 1 element" that occurred when Documenter.jl tried to execute plotting commands without access to the required solution variables.

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

Co-Authored-By: Claude <[email protected]>

Author: claude

docs/src/tutorials/sde_example.md

@@ -192,7 +192,7 @@ sol = SDE.solve(prob_sde_lorenz);
 nothing # hide
 ```
 
-```@example sde
+```@example sde2
 Plots.plot(sol, idxs = (1, 2, 3))
 ```
 
@@ -232,7 +232,7 @@ sol = SDE.solve(prob, SDE.SRIW1());
 nothing # hide
 ```
 
-```@example sde
+```@example sde3
 Plots.plot(sol)
 ```