feat: isolate explicit development server profiles

[pcvantol]

Summary

• add an explicit, machine-readable EP Server development profile without introducing a second installer authority
• require an isolated venv, data root, port, logs/cache roots, and development credential reference
• reject selected operational data roots, production service labels, operational credentials, and an identified operational interpreter
• propagate the profile through start/serve/restart and expose a redacted runtime identity in health

Validation

• python -m unittest discover -s tests -p test_*.py -q (1411 passing)
• engineering coverage: 84.49% total; development_profile.py: 88.18%
• fresh isolated wheel qualification and version-consistency check (2.3.2, sha256 9668a1d327d975802c8b4d007212d8ceaa965353bfaa5a69557c2db68eb379a4)
• generated development projection validation

Scope

Source-only change. It does not publish, install, cut over, alter services, or delete artifacts on the Mac.