Python: Fix Ollama approval resume message handling

[moonbox3]

Motivation & Context

AG-UI synthesizes a control-only user message when a user resumes an approved tool call. The Ollama connector rejected that message because it has no text or data content, preventing approval-gated tools from completing on AG-UI surfaces backed by Ollama.

Description & Review Guide

• What are the major changes? Ignore a user message composed solely of function approval responses when preparing Ollama model input, and add a regression test through the public OllamaChatClient.get_response() API.
• What is the impact of these changes? AG-UI approval resumes can continue through the Ollama connector; ordinary empty or unsupported user messages retain their existing validation behavior.
• What do you want reviewers to focus on? The narrow control-only condition and the regression transcript, which verifies that the normal user, assistant tool call, and tool result still reach Ollama.

Related Issue

Fixes #7451

Contribution Checklist

• The code builds clean without any errors or warnings
• All unit tests pass, and I have added new tests where possible
• The PR follows the Contribution Guidelines
• This PR is linked to an issue and there is no other open PR for this issue (see Related Issue above).
• This is not a breaking change. If it is a breaking change, add the breaking change label (or add "[BREAKING]" to the title prefix, before or after any language prefix) — a workflow keeps the label and title prefix in sync automatically.

[Copilot]

Pull request overview

Fixes an incompatibility between AG-UI’s synthesized approval-resume user messages and the Ollama connector by dropping control-only approval-resume messages during Ollama message formatting, and adds a regression test to ensure the rest of the transcript (user → assistant tool call → tool result) still reaches Ollama.

Changes:

• Skip role="user" messages that contain only function_approval_response content when formatting user messages for Ollama.
• Add a regression test validating the approval-resume message is omitted from the outgoing Ollama messages payload.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
python/packages/ollama/agent_framework_ollama/_chat_client.py	Drops control-only approval-resume user messages by returning an empty formatted message list.
python/packages/ollama/tests/test_ollama_chat_client.py	Adds a regression test asserting the approval-resume message is not forwarded to Ollama.

[github-actions]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/ollama/agent_framework_ollama
_chat_client.py	233	9	96%	404, 406, 417, 421–422, 437, 448, 530, 556
TOTAL	44049	4118	90%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
9068	34 💤	0 ❌	0 🔥	2m 27s ⏱️

[github-actions]

Automated Code Review

Reviewers: 5 | Confidence: 54% | Result: All clear

Reviewed: Correctness, Security Reliability, Test Coverage, Failure Modes, Design Approach

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Automated review by moonbox3's agents

[github-actions]

Automated Code Review

Reviewers: 4 | Confidence: 35% | Result: All clear

Reviewed: Correctness, Security Reliability, Failure Modes, Design Approach

---

Automated review by moonbox3's agents