Missing tests for several CLI commands

[AnupamKumar-1]

Most commands in packages/cli/src/commands/ have a matching test file (config.test.ts, incident.test.ts, init.test.ts, services.test.ts, start.test.ts, usage.test.ts), but these don't:

• ask.ts
• errors.ts
• export.ts
• logs.ts
• metrics.ts
• prune.ts
• traces.ts

CONTRIBUTING.md asks for new commands to ship with a <command>.test.ts — these just predate that.

prune.ts and errors.ts are the smallest, good place to start. services.test.ts / usage.test.ts show the pattern: spin up a temp SQLite store, run the command, check the output/state. One or two commands per PR is fine.