feat: whitepaper sections 2-6, README overhaul, SpeckDL spec v0.1, reference agent scaffold

- Dark Provenance whitepaper: complete sections 2-6 (What Is Dark Provenance,
  The Speckl Approach, Semantic Preservation & SA-11, Implications, Call to Action)
- README: public launch-ready with architecture, roadmap, getting started
- SpeckDL SPEC.md: v0.1 language specification with EBNF grammar,
  type system, compilation pipeline, 5 example Specks
- Reference agent: TypeScript scaffold with Orchestrator, TeamLead, SMEs
  (VerificationSME, CodegenSME), TillDone condition tracking,
  ProvenanceGraph, and CLI with example Specks

reference-agent/package.json

@@ -0,0 +1,22 @@
+{
+  "name": "@speckl/reference-agent",
+  "version": "0.1.0",
+  "description": "Reference Agent Architecture — Speckl's tiered agent harness",
+  "private": true,
+  "type": "module",
+  "scripts": {
+    "build": "tsc",
+    "start": "node dist/cli.js",
+    "dev": "npx tsx src/cli.ts",
+    "example": "npx tsx src/cli.ts",
+    "test": "node --experimental-vm-modules node_modules/.bin/jest"
+  },
+  "engines": {
+    "node": ">=18"
+  },
+  "devDependencies": {
+    "@types/node": "^20.0.0",
+    "typescript": "^5.4.0"
+  },
+  "dependencies": {}
+}