docs: ask for pictures in issues and pull requests

The bug template's Evidence asks for a screenshot or recording first,
marked up, and a section for meshes; the feature template gains a
Pictures field; the pull request template and CONTRIBUTING ask for
before/after pictures of any visible change.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

.github/ISSUE_TEMPLATE/bug.yml

@@ -24,7 +24,8 @@ body:
     id: evidence
     attributes:
       label: Evidence
-      description: Screenshots, log output, numbers. For a crash, attach the crash report (`fieldcraft-cli crashes`, then `crashes show <id>`).
+      description: |
+        Pictures first: for anything you can see (the view, a mesh, a panel, a plot), drag a screenshot or a short screen recording in here, and mark the problem on it. For a mesh, a section through it (`fieldcraft-cli snapshot … --section`) shows what the outside hides. Then log output and numbers. For a crash, attach the crash report (`fieldcraft-cli crashes`, then `crashes show <id>`).
   - type: textarea
     id: expected
     attributes:

.github/ISSUE_TEMPLATE/feature.yml

@@ -21,6 +21,11 @@ body:
     attributes:
       label: Expected behaviour
       description: What FieldCraft should do, as precisely as you can.
+  - type: textarea
+    id: pictures
+    attributes:
+      label: Pictures
+      description: A screenshot of where it would go, a sketch, or a picture of the result you are after. Drag images in here.
   - type: textarea
     id: reference
     attributes:

.github/pull_request_template.md

@@ -2,10 +2,14 @@ Closes #
 
 ## What and why
 
+## Before and after
+<!-- For any visible change (the view, meshes, panels, results, icons): a picture before and after. Drag them in here. -->
+
 ## How it was verified
 <!-- Tests added or changed; oracle cases (tests/oracle) for solver and meshing results, with their cited references. -->
 
 ## Checklist
 - [ ] The issue was assigned to me before I started (see CONTRIBUTING.md)
 - [ ] `cargo fmt --all`, `cargo clippy -p <crates I touched> --all-targets -- -D warnings` and their tests pass
+- [ ] Before/after pictures for any visible change
 - [ ] No code, text or data from GPL-family projects or commercial CAE products