feat(ext-api/foundation): add compat-floor CI gate script + touch-point data

Add scripts/check-compat-floor.py and research/touch-points data files
to foundation branch so CI compat-floor job passes on all stacked PRs.

Per PLAN.md §Compat-floor, all blast_radius ≥ 2.0 categories must have
complete test triples before v2 ships.

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

scripts/check-compat-floor.py

@@ -0,0 +1,111 @@
+#!/usr/bin/env python3
+"""
+Compat-floor gate: Verify all high-impact behavior categories have test triples.
+
+Per PLAN.md §Compat-floor: "Every blast_radius ≥ 2.0 pattern MUST pass v1 + v2 +
+migration tests before v2 ships."
+
+This script:
+1. Reads research/touch-points/behavior-categories.yaml
+2. Finds all categories with usage_weight >= 2.0 (blast_radius threshold)
+3. Checks that each has all three test files: bc-XX.v1.test.ts, bc-XX.v2.test.ts, bc-XX.migration.test.ts
+4. Exits 0 if all present, exits 1 if any missing (fails CI)
+
+Usage: python3 scripts/check-compat-floor.py
+"""
+
+import sys
+from pathlib import Path
+
+try:
+    import yaml
+except ImportError:
+    print("ERROR: PyYAML not installed. Run: pip install pyyaml", file=sys.stderr)
+    sys.exit(1)
+
+COMPAT_FLOOR_THRESHOLD = 2.0
+BEHAVIOR_CATEGORIES_PATH = Path("research/touch-points/behavior-categories.yaml")
+TESTS_DIR = Path("src/extension-api-v2/__tests__")
+
+def main():
+    # Check that behavior-categories.yaml exists
+    if not BEHAVIOR_CATEGORIES_PATH.exists():
+        print(f"ERROR: {BEHAVIOR_CATEGORIES_PATH} not found", file=sys.stderr)
+        print("       Run scripts/build-behavior-categories.py first or copy from workspace", file=sys.stderr)
+        sys.exit(1)
+
+    # Load categories
+    with open(BEHAVIOR_CATEGORIES_PATH, "r") as f:
+        data = yaml.safe_load(f)
+
+    categories = data.get("categories", [])
+
+    # Find categories above compat floor
+    above_floor = []
+    for cat in categories:
+        cat_id = cat.get("category_id", "")
+        usage_weight = cat.get("usage_weight", 0)
+        if usage_weight >= COMPAT_FLOOR_THRESHOLD:
+            above_floor.append({
+                "id": cat_id,
+                "name": cat.get("name", ""),
+                "usage_weight": usage_weight
+            })
+
+    print(f"Compat-floor check: {len(above_floor)} categories with usage_weight >= {COMPAT_FLOOR_THRESHOLD}")
+    print()
+
+    # Check each category for test triples
+    missing = []
+    for cat in above_floor:
+        cat_id = cat["id"]
+        # Extract number from BC.XX
+        num_str = cat_id.replace("BC.", "").zfill(2)
+
+        required_files = [
+            f"bc-{num_str}.v1.test.ts",
+            f"bc-{num_str}.v2.test.ts",
+            f"bc-{num_str}.migration.test.ts"
+        ]
+
+        cat_missing = []
+        for fname in required_files:
+            fpath = TESTS_DIR / fname
+            if not fpath.exists():
+                cat_missing.append(fname)
+
+        if cat_missing:
+            missing.append({
+                "category": cat_id,
+                "name": cat["name"],
+                "usage_weight": cat["usage_weight"],
+                "missing": cat_missing
+            })
+            status = "❌ MISSING"
+        else:
+            status = "✅"
+
+        print(f"  {cat_id} ({cat['usage_weight']:.2f}) {cat['name'][:40]:<40} {status}")
+        if cat_missing:
+            for m in cat_missing:
+                print(f"       └─ {m}")
+
+    print()
+
+    if missing:
+        print(f"FAIL: {len(missing)} categories missing test files", file=sys.stderr)
+        print()
+        print("Per PLAN.md §Compat-floor, all blast_radius >= 2.0 categories", file=sys.stderr)
+        print("must have complete test triples (v1, v2, migration) before v2 ships.", file=sys.stderr)
+        print()
+        print("Missing files:", file=sys.stderr)
+        for m in missing:
+            for f in m["missing"]:
+                print(f"  - {TESTS_DIR / f}", file=sys.stderr)
+        sys.exit(1)
+    else:
+        print(f"PASS: All {len(above_floor)} compat-floor categories have test triples")
+        sys.exit(0)
+
+if __name__ == "__main__":
+    main()