chore: add .env.example for environment variable template

.env.example

@@ -0,0 +1,32 @@
+# CodeTribunal — Environment Configuration
+# Copy this file to .env and fill in the values
+
+# Z.ai API key
+ZAI_API_KEY=
+
+# LLM model (default: zai/glm-5.1)
+MODEL_NAME=zai/glm-5.1
+
+# Z.ai API base endpoint (default: coding endpoint for GLM-5.1)
+ZAI_API_BASE=https://api.z.ai/api/coding/paas/v4
+
+# Generation settings
+TEMPERATURE=0.3
+MAX_TOKENS=4096
+
+# Evidence scanning
+GRIT_TIMEOUT=60
+MAX_FILE_SIZE_MB=50
+MAX_FILES=500
+EVIDENCE_CHUNK_SIZE=3000
+MAX_SCAN_WORKERS=4
+
+# Server
+SERVER_HOST=0.0.0.0
+SERVER_PORT=7860
+
+# Pipeline storage
+STORAGE_DIR=.tribunal_data
+
+# Disable OpenTelemetry
+OTEL_SDK_DISABLED=true