Flaky: specification-tools (1/90) and self-learning-rvf hang #45

Flaky and hanging tests found during the 3.5.0 triage (#42):

• tests/specification-tools.test.ts: one test fails intermittently. It passed 90/90 in 4 of 5 solo runs and failed once when the machine was under load (loadavg ~60). The parallel baseline reported STACK_TRACE_ERROR. A run takes ~47 s, so it is likely timing-sensitive. Capture the failing test name on the next failure.
• tests/backends/self-learning-rvf.test.ts: hangs before reporting any result. The worker sits at 0% CPU in a native futex wait, with the @ruvector/router and rvf-node modules loaded, and ./vectors.db gets created in the cwd. It reproduces on 3fcb850 with no changes, and once passed in 2.5 s, so it is intermittent. Suspect a lock in a native module during setup. @ruvector/router opens ./vectors.db with an exclusive lock when no storagePath is given.