feat: complete Phase 1 - vocabulary expansion & DriftProbe infrastructure

- CLI: nyx-probe scan with --summary/--delta/--full flags
- DriftProbe: training safety with Gini coefficient + Angular Drift
- Vocabulary: 54 terms (30 nimmerverse + 24 German philosophical)
- Sentinels: ANCHOR/BRIDGE/CANARY/TARGET monitoring system

Key findings:
- German philosophical terms: 37.5% depth≥2 hit rate (vs 3.3% nimmerverse)
- Super Cluster validated: heart cross-lang sim = 1.000
- Isolated Zone confirmed: being EN↔DE sim = 0.195
- Gini signature: Philosophy ~0.5 (diffuse), Technical ~0.8 (sparse)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

nyx_probing/core/__init__.py

@@ -0,0 +1,19 @@
+"""Core components for nyx-probing."""
+from .model import NyxModel, GenerationResult
+from .probe_result import (
+    EchoType,
+    ReadinessLevel,
+    SurfaceProbeResult,
+    EchoProbeResult,
+    ReadinessResult,
+)
+
+__all__ = [
+    "NyxModel",
+    "GenerationResult",
+    "EchoType",
+    "ReadinessLevel",
+    "SurfaceProbeResult",
+    "EchoProbeResult",
+    "ReadinessResult",
+]