Phase 1 cleanup: update settings.json to current schema, document venv activation in CLAUDE.md

.claude/settings.json

@@ -1,10 +1,5 @@
 {
-  "allowedTools": [
-    "Read", "Write", "Edit", "Bash", "Glob", "Grep", "WebFetch", "Task"
-  ],
-  "subagents": {
-    "environment-builder": { "description": "Builds sandbox, rubrics, server, client" },
-    "training-builder": { "description": "Builds GRPO and SFT training" },
-    "evaluator": { "description": "Builds evaluation, demos, results" }
+  "permissions": {
+    "allow": ["Read", "Write", "Edit", "Bash", "Glob", "Grep", "WebFetch", "Task"]
   }
 }

CLAUDE.md

@@ -26,5 +26,8 @@ If PROJECT.md doesn't cover something, stop and ask the user. Do not invent arch
 ## Dependencies
 openenv, trl, unsloth, pydantic>=2, fastapi, uvicorn, pytest, pytest-asyncio, wandb, datasets, huggingface_hub. Do not add others without asking.
 
+## Development setup
+Python 3.14 on Homebrew enforces PEP 668. A venv exists at .venv/ with pytest, pytest-asyncio, and ruff installed. Before running any tests or committing: source .venv/bin/activate. The pre-commit hook depends on this activation.
+
 ## Style
 Black for formatting, Ruff for linting, isort for imports. Configure in pyproject.toml.