phase 1: copy Kindred-only files onto upstream/main (FreeCAD 1.2.0-dev)

Wholesale copy of all Kindred Create additions that don't conflict with
upstream FreeCAD code:

- kindred-icons/ (1444 Catppuccin Mocha SVG icon overrides)
- src/Mod/Create/ (Kindred Create workbench)
- src/Gui/ Kindred source files (FileOrigin, OriginManager,
  OriginSelectorWidget, CommandOrigin, BreadcrumbToolBar, EditingContext)
- src/Gui/Icons/ (Kindred branding and silo icons)
- src/Gui/PreferencePacks/KindredCreate/
- src/Gui/Stylesheets/ (KindredCreate.qss, images_dark-light/)
- package/ (rattler-build recipe)
- docs/ (architecture, guides, specifications)
- .gitea/ (CI workflows, issue templates)
- mods/silo, mods/ztools submodules
- .gitmodules (Kindred submodule URLs)
- resources/ (kindred-create.desktop, kindred-create.xml)
- banner-logo-light.png, CONTRIBUTING.md

.gitea/pull_request_template.md

@@ -0,0 +1,18 @@
+## Summary
+
+<!-- Brief description of what this PR does -->
+
+## Changes
+
+<!-- List the key changes made -->
+
+## Related Issues
+
+<!-- Link related issues: Closes #123, Fixes #456 -->
+
+## Checklist
+
+- [ ] Commit messages follow [conventional commits](https://www.conventionalcommits.org/) (`feat:`, `fix:`, `chore:`, `docs:`, `art:`)
+- [ ] Code follows project style (clang-format for C++, black for Python)
+- [ ] Changes are tested locally
+- [ ] Documentation updated (if applicable)