🐛 fix bug with reasoning not being handled by a simple strategy (#1180)

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## Motivation and Context
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After the fix from @devcrocod we do need to update our example code
agent to use the explicit sequential strategy.

## Breaking Changes
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---

#### Type of the changes
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Bug fix (non-breaking change which fixes an issue)
- [ ] Breaking change (fix or feature that would cause existing
functionality to change)
- [ ] Documentation update
- [ ] Tests improvement
- [ ] Refactoring

#### Checklist
- [ ] The pull request has a description of the proposed change
- [ ] I read the [Contributing
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before opening the pull request
- [ ] The pull request uses **`develop`** as the base branch
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Author: BLannoo

examples/code-agent/step-01-minimal-agent/src/main/kotlin/Main.kt

@@ -1,6 +1,7 @@
 package ai.koog.agents.examples.codeagent.step01
 
 import ai.koog.agents.core.agent.AIAgent
+import ai.koog.agents.core.agent.ToolCalls
 import ai.koog.agents.core.agent.singleRunStrategy
 import ai.koog.agents.core.tools.ToolRegistry
 import ai.koog.agents.ext.tool.file.EditFileTool
@@ -25,7 +26,7 @@ val agent = AIAgent(
         Your goal is to deliver production-ready code changes that integrate seamlessly with the existing codebase and solve given task.
     """.trimIndent(),
 
-    strategy = singleRunStrategy(),
+    strategy = singleRunStrategy(ToolCalls.SEQUENTIAL),
     maxIterations = 100
 )
 {

examples/code-agent/step-02-add-execution-tool/src/main/kotlin/Main.kt

@@ -1,6 +1,7 @@
 package ai.koog.agents.examples.codeagent.step02
 
 import ai.koog.agents.core.agent.AIAgent
+import ai.koog.agents.core.agent.ToolCalls
 import ai.koog.agents.core.agent.singleRunStrategy
 import ai.koog.agents.core.tools.ToolRegistry
 import ai.koog.agents.ext.tool.file.EditFileTool
@@ -36,7 +37,7 @@ val agent = AIAgent(
         Verify your changes don't break existing functionality through regression testing, but prefer running targeted tests over full test suites.
         Note: the codebase may be fully configured or freshly cloned with no dependencies installed - handle any necessary setup steps.
         """.trimIndent(),
-    strategy = singleRunStrategy(),
+    strategy = singleRunStrategy(ToolCalls.SEQUENTIAL),
     maxIterations = 400
 ) {
     handleEvents {