feat: SOLPRISM verifiable reasoning for SAID agents

.env.example

@@ -6,3 +6,9 @@ SOLANA_RPC_URL="https://api.mainnet-beta.solana.com"
 
 # Server
 PORT=3001
+
+# SOLPRISM Integration (optional — verifiable reasoning commitments)
+# Set to "true" to enable reasoning traces for agent actions
+# SOLPRISM_ENABLED=true
+# SOLPRISM_AGENT_NAME=said-api
+# SOLPRISM_KEYPAIR_PATH=/path/to/solana-keypair.json

SOLPRISM.md

@@ -0,0 +1,125 @@
+# SOLPRISM × SAID Protocol Integration
+
+**Verifiable AI Reasoning for Agent Identity & Reputation**
+
+## What This Adds
+
+[SOLPRISM](https://github.com/basedmereum/axiom-protocol) is a commit-reveal protocol for verifiable AI reasoning on Solana. This integration adds **reasoning commitments** to key SAID Protocol actions, answering not just _"who is this agent?"_ but _"why did this agent act?"_.
+
+### The Synergy
+
+| SAID Protocol | SOLPRISM | Together |
+|--------------|----------|----------|
+| **Who** is this agent? | **Why** did the agent act? | Full trust profile |
+| Identity verification | Reasoning verification | Complete accountability |
+| Reputation scores | Decision audit trails | Trustworthy AI agents |
+
+## How It Works
+
+1. **Before** a key action (feedback, trust check, source event), SOLPRISM creates a reasoning trace documenting the decision logic
+2. The trace is hashed (SHA-256) and committed — this is the **pre-commitment**
+3. The action executes normally (zero changes to existing SAID logic)
+4. The hash can be verified later against the full reasoning trace
+
+```
+Agent submits feedback → SOLPRISM commits reasoning hash → SAID processes feedback → Hash verifiable forever
+```
+
+## Setup
+
+### 1. Environment Variables
+
+Add to your `.env`:
+
+```bash
+# Enable SOLPRISM reasoning commitments
+SOLPRISM_ENABLED=true
+SOLPRISM_AGENT_NAME=said-api
+
+# Optional: keypair for onchain commits (hash-only mode works without this)
+# SOLPRISM_KEYPAIR_PATH=/path/to/solana-keypair.json
+```
+
+### 2. No Code Changes Required
+
+The integration initializes automatically when `SOLPRISM_ENABLED=true` is set. If not set, everything works exactly as before — SOLPRISM is a pure opt-in addition.
+
+## What Gets Committed
+
+| SAID Action | SOLPRISM Trace | Why |
+|-------------|----------------|-----|
+| Feedback submission | Score, weight, verification status | Prove reputation updates are legitimate |
+| Trust verification | Trust tier calculation logic | Show how trust was determined |
+| Source feedback | Event type, score change, source | Audit platform-submitted reputation data |
+
+## API Response Enhancement
+
+When SOLPRISM is enabled, relevant API responses include a `solprism` field:
+
+```json
+{
+  "success": true,
+  "feedback": { ... },
+  "solprism": {
+    "hash": "a1b2c3d4...",
+    "timestamp": 1706000000000,
+    "actionType": "feedback"
+  }
+}
+```
+
+## Verification
+
+Anyone can verify a SOLPRISM commitment:
+
+```typescript
+import { hashTrace } from './src/solprism';
+
+// Given the original reasoning trace and the committed hash:
+const computedHash = hashTrace(trace);
+const isValid = computedHash === committedHash;
+// true = the reasoning was NOT tampered with
+```
+
+## Architecture
+
+```
+┌─────────────────────────────────────────────┐
+│                SAID API (Hono)              │
+│                                             │
+│  ┌─────────┐   ┌──────────┐   ┌─────────┐  │
+│  │Feedback │   │  Trust   │   │ Source  │  │
+│  │Endpoint │   │  Check   │   │Feedback │  │
+│  └────┬────┘   └────┬─────┘   └────┬────┘  │
+│       │              │              │        │
+│       ▼              ▼              ▼        │
+│  ┌──────────────────────────────────────┐   │
+│  │     SolprismIntegration (optional)   │   │
+│  │  - Creates reasoning traces          │   │
+│  │  - Hashes & commits pre-action       │   │
+│  │  - Zero impact if disabled           │   │
+│  └──────────────────────────────────────┘   │
+│                     │                        │
+└─────────────────────┼────────────────────────┘
+                      │
+                      ▼
+          ┌──────────────────────┐
+          │  SOLPRISM Program    │
+          │  (Solana Devnet)     │
+          │  CZcvor...QeBu      │
+          └──────────────────────┘
+```
+
+## Links
+
+- **SOLPRISM SDK**: [`@solprism/sdk@0.1.0`](https://github.com/basedmereum/axiom-protocol/tree/main/sdk)
+- **SOLPRISM Program**: `CZcvoryaQNrtZ3qb3gC1h9opcYpzEP1D9Mu1RVwFQeBu`
+- **Integration Source**: `src/solprism.ts`
+
+## Zero Risk
+
+- ✅ No changes to existing SAID business logic
+- ✅ Graceful no-op when disabled
+- ✅ No new runtime dependencies required
+- ✅ Uses crypto module already available in Node.js
+- ✅ No breaking changes to any API contract