fix: tighten captain v2 (#14883)

# Pull Request Template

## Description

Tightens v2 prompt and config to match v1

## Type of change

Please delete options that are not relevant.

- [x] Bug fix (non-breaking change which fixes an issue)


## How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide
instructions so we can reproduce. Please also list any relevant details
for your test configuration.
locally

## Checklist:

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [x] Any dependent changes have been merged and published in downstream
modules

spec/enterprise/services/captain/assistant/agent_runner_service_spec.rb

@@ -93,7 +93,7 @@ RSpec.describe Captain::Assistant::AgentRunnerService do
       expect(mock_runner).to receive(:run).with(
         'I need help with my account',
         context: expected_context,
-        max_turns: 100
+        max_turns: 10
       )
 
       service.generate_response(message_history: message_history)
@@ -119,7 +119,7 @@ RSpec.describe Captain::Assistant::AgentRunnerService do
           expect(input.text).to eq('What does this error mean?')
           expect(input.attachments.first.source.to_s).to eq('https://example.com/error.png')
           expect(context[:conversation_history]).to eq([{ role: :assistant, content: 'Please share a screenshot', agent_name: nil }])
-          expect(max_turns).to eq(100)
+          expect(max_turns).to eq(10)
         end
 
         service.generate_response(message_history: multimodal_message_history)
@@ -147,7 +147,7 @@ RSpec.describe Captain::Assistant::AgentRunnerService do
             { type: 'text', text: 'Here is my error screenshot' },
             { type: 'image_url', image_url: { url: 'https://example.com/error.png' } }
           )
-          expect(max_turns).to eq(100)
+          expect(max_turns).to eq(10)
         end
 
         service.generate_response(message_history: history_with_prior_image)
@@ -157,7 +157,7 @@ RSpec.describe Captain::Assistant::AgentRunnerService do
         expect(mock_runner).to receive(:run) do |_input, context:, max_turns:|
           expect(context[:captain_v2_trace_input]).to include('image_url')
           expect(context[:captain_v2_trace_current_input]).to include('image_url')
-          expect(max_turns).to eq(100)
+          expect(max_turns).to eq(10)
         end
 
         service.generate_response(message_history: multimodal_message_history)