feat: Add experiments framework and novelty-driven agent loop

- Add complete experiments directory with pilot study infrastructure
  - 5 experimental conditions (direct, expert-only, attribute-only, full-pipeline, random-perspective)
  - Human assessment tool with React frontend and FastAPI backend
  - AUT flexibility analysis with jump signal detection
  - Result visualization and metrics computation

- Add novelty-driven agent loop module (experiments/novelty_loop/)
  - NoveltyDrivenTaskAgent with expert perspective perturbation
  - Three termination strategies: breakthrough, exhaust, coverage
  - Interactive CLI demo with colored output
  - Embedding-based novelty scoring

- Add DDC knowledge domain classification data (en/zh)
- Add CLAUDE.md project documentation
- Update research report with experiment findings

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

experiments/data/queries.json

@@ -0,0 +1,66 @@
+{
+  "description": "10 pilot queries for the 5-condition experiment, balanced across categories",
+  "version": "1.0",
+  "queries": [
+    {
+      "id": "A1",
+      "query": "Chair",
+      "category": "everyday",
+      "description": "Common household furniture"
+    },
+    {
+      "id": "A5",
+      "query": "Bicycle",
+      "category": "everyday",
+      "description": "Personal transportation device"
+    },
+    {
+      "id": "A7",
+      "query": "Smartphone",
+      "category": "everyday",
+      "description": "Mobile communication device"
+    },
+    {
+      "id": "B1",
+      "query": "Solar panel",
+      "category": "technology",
+      "description": "Renewable energy technology"
+    },
+    {
+      "id": "B3",
+      "query": "3D printer",
+      "category": "technology",
+      "description": "Additive manufacturing device"
+    },
+    {
+      "id": "B4",
+      "query": "Drone",
+      "category": "technology",
+      "description": "Unmanned aerial vehicle"
+    },
+    {
+      "id": "C1",
+      "query": "Food delivery service",
+      "category": "services",
+      "description": "Restaurant meal delivery platform"
+    },
+    {
+      "id": "C2",
+      "query": "Online education platform",
+      "category": "services",
+      "description": "Digital learning service"
+    },
+    {
+      "id": "C4",
+      "query": "Public transportation",
+      "category": "services",
+      "description": "Mass transit system"
+    },
+    {
+      "id": "C9",
+      "query": "Elderly care service",
+      "category": "services",
+      "description": "Senior citizen support service"
+    }
+  ]
+}