Split native Periscope (periscope/src) from inherited PinScope (periscope/dependency).

Keep validate.py and the finding engine as-is. AGPL LICENSE stays at the repo root.
Docker overlays dependency then src. Do not delete the inherited tree.

tests/test_validation_no_tool_recovery.py

@@ -9,6 +9,8 @@ so it survives future prompt regressions.
 
 from __future__ import annotations
 
+from tests.paths import SIMPLE_PROJECT, TAXONOMY
+
 import json
 from pathlib import Path
 
@@ -20,7 +22,7 @@ from backend.services import validation as val
 from backend.services.llm.types import Completion, ToolCall, Usage
 from backend.services.storage import LocalStorageBackend
 
-GRAPH = Path(__file__).resolve().parent.parent / "simple_project" / "design_graph.json"
+GRAPH = SIMPLE_PROJECT / "design_graph.json"
 IC_MPNS = {
     "U1": "SPX3819M5-L-3-3/TR",
     "U2": "CH340E",