remove redundant marauder wrappers and anthropic dependency

memory.py and marauder_cart.py were subprocess wrappers around marauder
CLI — redundant now that the opencode chat agent has native EEMS tools.
Also remove custom TOOLS dict, EEMS context injection at session start,
marauder_cart.create() in calibration_done, and anthropic dep/env vars.
Inline slug() as _slug() in calibration.py.

.env.example

@@ -1,10 +1,12 @@
 # Required
-ANTHROPIC_API_KEY=sk-ant-...
 GOOGLE_CLIENT_ID=000000000000-xxxxxxxxxxxxxxx.apps.googleusercontent.com
 GOOGLE_CLIENT_SECRET=GOCSPX-xxxxxxxxxxxxx
+OPENCODE_PASSWORD=...
 
 # Optional — defaults shown
-ANTHROPIC_MODEL=claude-sonnet-4-5-20250929
+OPENCODE_URL=http://sin:4096
+OPENCODE_MODEL=cyankiwi/qwen3-coder-next:awq
+OPENCODE_PROVIDER=vllm
 BASE_URL=https://chat.saiden.dev
 ALLOWED_EMAILS=adam.ladachowski@gmail.com
 # COOKIE_SECURE=false   # set this only for local http dev