fix(fault_manager): make rosbag capture enablement crash-safe

[mfaferek93]

Enabling black-box rosbag capture is the exact path that can crash the fault_manager on startup. RosbagCapture's constructor validates the storage format by opening a throwaway bag, which throws std::runtime_error when the storage plugin (e.g. rosbag2_storage_mcap) is not available at runtime. That construction in fault_manager_node.cpp is not wrapped in try/catch and main.cpp has none either, so the exception propagates out of main and terminates the process. The published Docker image does not install rosbag2_storage_mcap, so a user who sets snapshots.rosbag.enabled:=true with the default format hits this.

Compounding: the default storage format is mcap in code but the shipped YAML config documents sqlite3, so code and docs disagree on what a user actually gets.

Scope

• Wrap the RosbagCapture construction so a storage/format failure disables rosbag capture and logs a clear warning instead of terminating the node.
• Reconcile the default storage format so the code and the YAML config agree.
• Either ship the storage plugin in the binary/Docker distribution or default to a format that needs no extra plugin, so enabling capture works out of the box.

Acceptance

• With snapshots.rosbag.enabled:=true and the storage plugin absent, the fault_manager stays up, logs a warning, and continues without rosbag capture.
• The default storage format is identical in code and in the shipped config.