feat(tools): reset_circuit_breaker tool — let the caller clear an open breaker instead of waiting out recovery_timeout #115

Problem

When a tool fails repeatedly, CircuitBreakerAdapter (adapters/circuit_breaker.py) trips that operation's per-op bucket (_BreakerBucket; 5 failures → OPEN) and rejects every later call with Circuit breaker is open for <tool> until recovery_timeout (60 s) elapses. See runbook item #4 in CLAUDE.md.

In Claude sessions this is often a pure wait. The LLM has already stopped retrying and fixed the cause, for example a wrong argument, a dismissed SolidWorks dialog, or a reopened document. It still can't make the next call for up to a minute, and the only workaround is a server restart.

Proposed solution

Add a reset_circuit_breaker MCP tool:

• Input: operation: str | None = None. Pass a name to reset one bucket, or None to reset all buckets plus the legacy/default bucket used by connect().
• Reset means state=CLOSED, failure_count=0, half_open_calls=0.
• Return the state before and after for each affected bucket (name, state, failure_count, seconds since the last failure). The caller can then see what was open.
• Add a read-only companion, get_circuit_breaker_status (or include it in the same tool with dry_run). It lists the buckets that are open or half-open, so the LLM can tell it's blocked by the breaker and not by SolidWorks.
• Go through the adapter abstraction:
  • Add reset_circuit_breaker / get_circuit_breaker_status to base.py as no-op defaults. They report "no circuit breaker in this adapter chain".
  • Implement them in circuit_breaker.py.
  • Delegate through connection_pool.py, which may wrap the breaker.
• The reset tool must never be blocked by a breaker itself: no breaker bucket for this operation.

Acceptance criteria

• After a breaker trips for operation X, reset_circuit_breaker(operation="X") lets the next X call through immediately, without waiting for recovery_timeout
• reset_circuit_breaker() with no argument clears every bucket
• Resetting an unknown or closed operation succeeds and reports no change
• Status and reset work through the server's real adapter wrapping (pool → breaker → pywin32/mock)
• Unit tests in mock mode, plus a live test that trips a breaker with a deliberately failing call against real SolidWorks, resets it, and confirms the next call reaches SW
• CLAUDE.md runbook feat(adapter): implement sweep and loft COM operations in pywin32_adapter #4 and the tool catalog updated to mention the tool

Notes

Queued as item 5 after #106, #101, #98 and #105 (2026-10-13).