chore: standardize dashboard port to 8081 across launchers

- start.ps1 fallback 8080 -> 8081 (reads data/settings.json which is now 8081)
- server.py argparse --port default 8080 -> 8081 (bare server.py lands on 8081)
- (desktop Agentic OS.url already points at 127.0.0.1:8081; settings.json
  change kept local since it's git-ignored with api_keys)

Single consistent port story across WSL start.sh, Windows start.ps1,
bare server.py, and the desktop shortcut.

server.py

@@ -2645,7 +2645,7 @@ if __name__ == "__main__":
     import uvicorn
 
     parser = argparse.ArgumentParser()
-    parser.add_argument("--port", type=int, default=8080)
+    parser.add_argument("--port", type=int, default=8081)
     parser.add_argument("--host", type=str, default="0.0.0.0")
     args = parser.parse_args()
 

start.ps1

@@ -37,7 +37,7 @@ $pythonArgs = @($python.Args)
 & $pythonCommand @pythonArgs -m pip install -r requirements.txt --quiet
 
 $configuredPort = & $pythonCommand @pythonArgs -c "import json; f=open('data/settings.json'); d=json.load(f); print(int(d.get('dashboard',{}).get('port',8080))); f.close()" 2>$null
-if (-not $configuredPort) { $configuredPort = "8080" }
+if (-not $configuredPort) { $configuredPort = "8081" }
 $configuredPort = [int]$configuredPort
 
 function Find-FreePort {