Product repository template

Layout, proplan.toml, README/CHANGELOG, placeholder product image, .gitignore, KiBot/release/docgen workflows and TEMPLATE.md. Source of truth: contrib/product-template in B4L/proplan (cargo test --test product_template checks it as Gitea 1.27 creates a repository from it).

.gitignore

@@ -0,0 +1,37 @@
+# KiCad: backups, locks, local settings, caches
+*-backups/
+*.kicad_prl
+*.lck
+*.bak
+*.bck
+*.kicad_pcb-bak
+*.kicad_sch-bak
+_autosave-*
+fp-info-cache
+\#auto_saved_files\#
+
+# FreeCAD backups
+*.FCBak
+*.FCStd1
+
+# IDE build output and tool caches
+Debug/
+Release/
+build/
+__pycache__/
+*.pyc
+.venv/
+node_modules/
+.history/
+.claude/
+.vscode/
+.idea/
+
+# Generated output: CI builds it and attaches it to the release
+Generated/
+Fabrication/
+kibot_output_*/
+
+# OS
+.DS_Store
+Thumbs.db