Manage opencode 1.x config via home-manager and isolate opencode2

- Symlink ~/.config/opencode/opencode.json and skills/ from dotfiles
  so opencode 1.x config survives rebuild with zap cleanup
- Track cloud-deploy, cloudflared, github-cli, no-mistakes,
  playwright-cli, and read-tweet skills in repo
- Update opencode2 model to opencode/muse-spark-1.2-contributor-free
- Rotate opencode.json/skills in rebuild.sh alongside existing
  managed paths

home/.config/opencode/opencode.json

@@ -0,0 +1,33 @@
+{
+  "$schema": "https://opencode.ai/config.json",
+  "model": "opencode/muse-spark-1.2-contributor-free",
+  "instructions": ["AGENTS.md"],
+  "provider": {
+    "omlx": {
+      "npm": "@ai-sdk/openai-compatible",
+      "name": "oMLX (Local)",
+      "options": {
+        "baseURL": "http://localhost:8000/v1",
+        "apiKey": "none"
+      },
+      "models": {
+        "qwen3.6-35b": {
+          "id": "Jundot/Qwen3.6-35B-A3B-oQ4-mtp",
+          "name": "Qwen 3.6 35B (o4-mtp)",
+          "tool_call": true,
+          "limit": {
+            "context": 65536,
+            "output": 65536
+          }
+        }
+      }
+    }
+  },
+  "plugin": ["/Users/laptran/.automaton/plugins/automaton-guard"],
+  "command": {
+    "no-mistakes": {
+      "description": "Validate code changes through the no-mistakes pipeline",
+      "template": "Read $HOME/.config/opencode/skills/no-mistakes/SKILL.md and follow it. User request: {{args}}"
+    }
+  }
+}