chore(pi): update agent settings for new provider and model

- Switch default provider to opencode-go, model to deepseek-v4-flash
- Raise default thinking level from minimal to high
- Add terminal progress setting
- Bump last changelog version to 0.81.0

config/pi/agent/settings.json

@@ -1,9 +1,9 @@
 {
-  "lastChangelogVersion": "0.80.7",
+  "lastChangelogVersion": "0.81.0",
   "theme": "light/dark",
-  "defaultProvider": "github-copilot",
-  "defaultModel": "gpt-5-mini",
-  "defaultThinkingLevel": "minimal",
+  "defaultProvider": "opencode-go",
+  "defaultModel": "deepseek-v4-flash",
+  "defaultThinkingLevel": "high",
   "hideThinkingBlock": true,
   "compaction": {
     "enabled": true
@@ -58,5 +58,8 @@
     }
   },
   "quietStartup": true,
-  "steeringMode": "all"
+  "steeringMode": "all",
+  "terminal": {
+    "showTerminalProgress": true
+  }
 }