Add OpensearchRemoteLogIO.from_config and register opensearch scheme

[FrankYang0529]

Why

#67056 decoupled remote logging from the hardcoded branches in airflow_local_settings.py: core and the Task SDK now resolve the handler via ProvidersManager dispatch on the [logging] remote_base_log_folder URL scheme. This migrates the opensearch scheme.

How

• Add OpensearchRemoteLogIO.from_config() reading the [opensearch] section — a mirror of the legacy branch, so the user-facing config surface is unchanged.
• Register the opensearch scheme in provider.yaml.

Verify

• uv run --project providers/opensearch pytest providers/opensearch/tests/unit/opensearch/log/test_os_task_handler.py
• end to end test

# 1. Create config
mkdir -p files/airflow-breeze-config
cat > files/airflow-breeze-config/environment_variables.env <<'EOF'
export AIRFLOW__LOGGING__REMOTE_LOGGING=True
export AIRFLOW__LOGGING__REMOTE_BASE_LOG_FOLDER=opensearch://
export AIRFLOW__OPENSEARCH__HOST=http://opensearch:9200
export AIRFLOW__OPENSEARCH__PORT=9200
export AIRFLOW__OPENSEARCH__WRITE_TO_OS=True
export AIRFLOW__OPENSEARCH__JSON_FORMAT=True
export AIRFLOW__OPENSEARCH__WRITE_STDOUT=False
export AIRFLOW__OPENSEARCH__TARGET_INDEX=airflow-logs
EOF

# 2. Start Airflow
breeze start-airflow --integration opensearch --backend postgres --load-example-dags

# 3. Run Dag
airflow dags unpause example_bash_operator
airflow dags trigger example_bash_operator
airflow dags list-runs example_bash_operator

# 4. Check log
curl -s localhost:9200/airflow-logs/_count ; echo
curl -s 'localhost:9200/airflow-logs/_search?q=log_id:example_bash_operator&size=3'

• closes: Add OpensearchRemoteLogIO.from_config and register opensearch scheme #70272
• related: Provider migration for decoupling remote logging from core #70265

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Was generative AI tooling used to co-author this PR?

• Yes - Claude Code

---

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