feat(template): add CODEOWNERS and a pull request template

New satellites start with the maintainers team as code owners and a short
PR template: title convention, develop as the target, validator and tests,
cited sources, and the sidebar filled in by hand. Issue templates are left
to the organisation's shared ones. The template validator's docstring no
longer quotes game-catalog's record count.

Author: Seungpyo1007

machine/satellite_template/.github/CODEOWNERS

@@ -0,0 +1,2 @@
+# Default owners for everything in this repository.
+* @GetTechAPI/maintainers

machine/satellite_template/.github/pull_request_template.md

@@ -0,0 +1,12 @@
+<!-- PR title follows Conventional Commits, e.g. data({{category}}): add <name>. Target `develop`; only a release PR targets `main`. -->
+
+## What & why
+
+<!-- What does this change and why? Use "Closes #123" for the issue it resolves. -->
+
+## Checklist
+
+- [ ] Targets `develop`
+- [ ] `python -m app.validate` and `python -m pytest -q` pass locally
+- [ ] Every new or changed record cites at least one public reference in `source_urls`
+- [ ] Sidebar filled in by hand: assignees, labels, milestone, projects

machine/satellite_template/app/validate.py

@@ -2,7 +2,7 @@
 
 Generated by TechMachine's satellite template. Records are checked one at a
 time rather than loaded into a list first, so the check scales to catalogs of
-any size (game-catalog validates ~1M records in about 90 seconds on CI).
+any size.
 
 Run with: python -m app.validate
 """