agents: raise theo reasoning to high with thinking budget

Theo is a security auditor reasoning about injection, TOCTOU races,
crypto misuse, and confused-deputy problems — adversarial edge-case work
that needs deep deliberation, not the low effort it was set to. Bump to
reasoningEffort=high and add thinkingBudget=16384 so depth carries over
to Anthropic extended thinking. Raise maxTokens to 24576 so it stays
above the thinking budget (Anthropic requires budget < max_tokens).

data/agents/theo.json

@@ -26,6 +26,7 @@
     "lsp_diagnostics"
   ],
   "temperature": 0.3,
-  "maxTokens": 8192,
-  "reasoningEffort": "low"
+  "maxTokens": 24576,
+  "reasoningEffort": "high",
+  "thinkingBudget": 16384
 }