Add global DELETE /api/v1/faults endpoint (extension)

[mfaferek93]

Summary

The gateway provides GET /api/v1/faults as a convenience endpoint to list all faults across the system (regardless of entity ownership). However, there is no corresponding DELETE /api/v1/faults to clear all faults globally.

Per-entity DELETE /api/v1/{entity-path}/faults only clears faults owned by that entity. Faults reported via ROS 2 service with arbitrary source_id values aren't owned by any manifest entity, so per-entity DELETE can't clear them.

Note: This is a ros2_medkit extension, not part of the SOVD standard. SOVD is entity-centric - fault operations are scoped to entities. Our GET /api/v1/faults is already an extension; this adds the matching write operation.

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Proposed solution

DELETE /api/v1/faults

Clear all faults in the system, regardless of entity ownership.

Response 204 No Content on success.

Optional query parameter:

Parameter	Type	Required	Description
status	string	No	Filter which faults to clear: confirmed, prefailed, all (default: confirmed)

Example:

# Clear all confirmed faults
curl -X DELETE "http://localhost:8080/api/v1/faults"

# Clear everything (including prefailed)
curl -X DELETE "http://localhost:8080/api/v1/faults?status=all"

Implementation

The fault manager already has a ClearFault service per fault code. The global DELETE handler should:

1. Call GET /api/v1/faults (internal) to get all fault codes
2. Call ClearFault for each fault code
3. Return 204 when all clears complete

Alternatively, add a ClearAllFaults ROS 2 service to fault_manager_node for atomic bulk clear.

Route registration

// Extension: global fault management (not SOVD - convenience API)
srv->Delete(api_path("/faults"), handler);

Documentation

Mark clearly as extension in docs/api/rest.rst:

.. note::

   ``DELETE /api/v1/faults`` is a ros2_medkit extension, not part of the
   SOVD standard. SOVD fault operations are entity-scoped.

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Additional context

Current workaround: Restart fault_manager_node with storage_type:=memory (memory is wiped on restart).

Files to modify

• src/ros2_medkit_gateway/src/http/rest_server.cpp - Register DELETE route
• src/ros2_medkit_gateway/src/http/handlers/fault_handlers.cpp - Implement handler
• src/ros2_medkit_fault_manager/src/fault_manager_node.cpp - Optional: add ClearAllFaults service
• src/ros2_medkit_msgs/srv/ - Optional: ClearAllFaults.srv
• docs/api/rest.rst - Document endpoint with extension note
• Unit tests + integration test

Acceptance criteria

• DELETE /api/v1/faults clears all faults regardless of entity ownership
• Optional status query parameter filters which faults to clear
• Response is 204 No Content
• Documented as ros2_medkit extension (not SOVD)
• Unit test: clear all confirmed faults
• Unit test: clear with status=all includes prefailed
• Integration test: inject faults via service - DELETE - verify empty