chore: bootstrap project scaffolding

Add architecture doc (research-wiki/ARCHITECTURE.md), CLAUDE.md with
tiered SOP for Fable 5, adapted .claude skills/hooks/settings, package
skeleton (src/polygateway), pyproject with import-linter contracts,
Makefile, .env.example and smoke test.

.claude/settings.json

@@ -0,0 +1,39 @@
+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "bash \"$CLAUDE_PROJECT_DIR\"/.claude/scripts/hooks/pre-tool-guard.sh"
+          },
+          {
+            "type": "command",
+            "command": "bash \"$CLAUDE_PROJECT_DIR\"/.claude/scripts/hooks/pre-commit-guard.sh"
+          }
+        ]
+      },
+      {
+        "matcher": "Write|Edit|MultiEdit|NotebookEdit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "bash \"$CLAUDE_PROJECT_DIR\"/.claude/scripts/hooks/pre-tool-guard.sh"
+          }
+        ]
+      }
+    ],
+    "PostToolUse": [
+      {
+        "matcher": "Write|Edit|MultiEdit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "bash \"$CLAUDE_PROJECT_DIR\"/.claude/scripts/hooks/post-edit-quality.sh"
+          }
+        ]
+      }
+    ]
+  }
+}