chore: move agent routing to OpenCode Go; add firstmate tooling

- crew-dispatch.json: route crew tasks to OpenCode Go models
- opencode/opencode2: pin opencode-go/gpt-6-luna
- grok: default to grok-4.5 with high reasoning, permission auto
- home.nix: axiTools activation for the *-axi CLIs; crewmate harness
  opencode; no-mistakes agent list opencode-only

home/.config/firstmate/crew-dispatch.json

@@ -1,20 +1,20 @@
 {
   "rules": [
     {
-      "when": "pure-function implementation with tests (indicators, slots, seasonal wiring, repositories)",
-      "use": [{ "harness": "pi", "model": "opencode-go/mimo-v2.5-pro" }],
-      "why": "MiMo V2.5 Pro (opencode-go, 1M ctx) produces clean correct code; flat-rate sub so $0 marginal cost. Pi drives it in an isolated worktree."
+      "when": "Well-specified implementation with clear acceptance criteria: pure functions, tests, repositories, adapters, or external-fetch integration.",
+      "use": [{ "harness": "opencode", "model": "opencode-go/deepseek-v4.1-flash", "provider": "opencode-go" }],
+      "why": "DeepSeek V4.1 Flash is the default OpenCode Go implementation worker; it is fast, economical, and strong on agentic coding tasks."
     },
     {
-      "when": "adapter or external-fetch integration (COT, seed backfills, vendor seams)",
-      "use": [{ "harness": "pi", "model": "opencode-go/mimo-v2.5-pro" }],
-      "why": "Pattern-following work against existing adapter contracts; MiMo handles iterative fetch/debug loops."
+      "when": "UI work where supplied screenshots or other image context materially affect the implementation or verification.",
+      "use": [{ "harness": "opencode", "model": "opencode-go/glm-5.3-flash", "provider": "opencode-go" }],
+      "why": "GLM-5.3-Flash is the Go worker with image input; use it when visual context matters."
     },
     {
-      "when": "frontend page or tRPC wiring (UI panels, router procedures, client exposure)",
-      "use": [{ "harness": "pi", "model": "opencode-go/mimo-v2.5-pro" }],
-      "why": "Mechanical wiring against existing components/routers; the contract carries the specialization."
+      "when": "Ambiguous investigation, difficult debugging, architectural tradeoffs, or broad changes with high uncertainty or blast radius.",
+      "use": [{ "harness": "opencode", "model": "opencode-go/gpt-6-luna", "provider": "opencode-go" }],
+      "why": "Reserve GPT-6 Luna for work that benefits from stronger reasoning than the fast implementation tier."
     }
   ],
-  "default": [{ "harness": "pi", "model": "opencode-go/mimo-v2.5-pro" }]
-}
+  "default": [{ "harness": "opencode", "model": "opencode-go/deepseek-v4.1-flash", "provider": "opencode-go" }]
+}