Polish config enforcement output and update examples

[CCimen]

Improved enforcement honesty and validation output in the CLI, and aligned templates/examples with the official marketplace naming.

• Changes: scc/src/scc_cli/application/compute_effective_config.py and scc/src/scc_cli/commands/config.py
  now surface enforcement status (enforced/partial/advisory/out‑of‑scope) with clearer warnings for
  network policy and MCP scope.
• Changes: validation and explain outputs were tightened in scc/src/scc_cli/validate.py, scc/src/scc_cli/
  commands/org/validate_cmd.py, and scc/src/scc_cli/commands/team.py to match actual enforcement
  behavior.
• Changes: init template and examples standardized marketplace naming in scc/src/scc_cli/commands/
  init.py, scc/examples/*.json, and scc/examples/README.md.
• Changes: tests added/updated for the new config/explain/validate behavior in scc/tests/
  test_config_validate.py, scc/tests/test_config_inheritance.py, scc/tests/test_org_cli.py, scc/tests/
  test_team_cli.py, and scc/tests/test_start_dryrun.py.
• Tests: uv run ruff format, uv run ruff check, uv run mypy src, uv run pytest.