What does this PR do?

Fixes the live in-process _send_via_adapter() path so gateway adapters receive media_files and force_document just like the existing standalone sender path. Before this change, attachments could silently disappear whenever the gateway runner and adapter lived in the current process.

Related Issue

Fixes #23760

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)
• ✨ New feature (non-breaking change that adds functionality)
• 🔒 Security fix
• 📝 Documentation update
• ✅ Tests (adding or improving test coverage)
• ♻️ Refactor (no behavior change)
• 🎯 New skill (bundled or hub)

Changes Made

• Forwarded media_files and force_document through the live adapter.send(...) call in /tools/send_message_tool.py
• Added a regression test in /tests/tools/test_send_message_tool.py that exercises the live in-process adapter path and asserts both kwargs are preserved

How to Test

1. Run uv run --frozen pytest -q -o addopts='' tests/tools/test_send_message_tool.py -k TestSendViaAdapterStandaloneFallback
2. Confirm the new test_live_adapter_forwards_media_kwargs passes
3. Run uv run --frozen ruff check tools/send_message_tool.py tests/tools/test_send_message_tool.py

Checklist

Code

• I've read the Contributing Guide
• My commit messages follow Conventional Commits (fix(scope):, feat(scope):, etc.)
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this fix/feature (no unrelated commits)
• I've run pytest tests/ -q and all tests pass
• I've added tests for my changes (required for bug fixes, strongly encouraged for features)
• I've tested on my platform: macOS 15 / local targeted pytest and ruff

Documentation & Housekeeping

• I've updated relevant documentation (README, docs/, docstrings) — or N/A
• I've updated cli-config.yaml.example if I added/changed config keys — or N/A
• I've updated CONTRIBUTING.md or AGENTS.md if I changed architecture or workflows — or N/A
• I've considered cross-platform impact (Windows, macOS) per the compatibility guide — or N/A
• I've updated tool descriptions/schemas if I changed tool behavior — or N/A

Screenshots / Logs

• uv run --frozen pytest -q -o addopts='' tests/tools/test_send_message_tool.py -k TestSendViaAdapterStandaloneFallback -> 6 passed
• uv run --frozen ruff check tools/send_message_tool.py tests/tools/test_send_message_tool.py -> passed