docs: initialize SportsTime Data Pipeline

Fix data quality issues across MLB, NBA, NHL, NFL with correct game→team→stadium canonical linking.

Creates PROJECT.md with requirements and constraints.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.planning/config.json

@@ -0,0 +1,18 @@
+{
+  "mode": "yolo",
+  "depth": "standard",
+  "gates": {
+    "confirm_project": false,
+    "confirm_phases": false,
+    "confirm_roadmap": false,
+    "confirm_breakdown": false,
+    "confirm_plan": false,
+    "execute_next_plan": false,
+    "issues_review": false,
+    "confirm_transition": false
+  },
+  "safety": {
+    "always_confirm_destructive": true,
+    "always_confirm_external_services": true
+  }
+}