feat: OPE46-00031: QoL: Add config management commands

[andrei-hasna]

Objective

OPE46-00031: QoL: Add config management commands

Add config management: monitor config edit, monitor config validate, monitor config backup, monitor config restore

MEASURED on origin/main: there is NO top-level config command in src/cli/index.ts. Config loading/writing already lives in src/config.ts. Add monitor config edit (open $EDITOR on the config path), monitor config validate (schema-check, non-zero exit on invalid), monitor config backup and monitor config restore (timestamped copies next to the config file).

EXECUTION NOTES (added 2026-07-29 for autonomous execution)
Repo: github.com/hasna/monitor. CLI commands are registered in src/cli/index.ts (Commander). Verified against origin/main that this surface does NOT already exist.
Requirements: implement in src/ (not docs); keep existing output shapes and the -j/--json contract intact; reuse the existing helpers in that file (parseLimitOption, parseCursorOption, chalk formatting) rather than inventing new patterns.
Acceptance: bun run typecheck, bun run build and bun test are all green, and a new/extended test under src/ exercises the new behaviour (assert on the command's JSON output and/or exit code, not on colored text). No network, no live remote machines, no credentials — tests must run offline against local collectors/fixtures.

Verification

• policy source: base c4cbd1e (immutable commit — agent-proof)
• ⚠️ GATE-INTEGRITY: agent touched verify-bearing config — REVIEW (scripts.typecheck)
• containment: env — allowlist env, non-login shell, run-scoped HOME (registry auth seeded for install)
• install: pass
• typecheck: pass
• lint: pass
• build: pass
• test: pass
• doctor (ci): ok — 11 checks passed (1 advisory)

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Run run_eaf46d73a19c · backend codewith · task 48df279c-6c90-44fa-8abc-f640e11ef1b4
🏭 Generated by @hasnaxyz/factory

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