feat: OPE46-00040: QoL: Add batch kill operations

[andrei-hasna]

Objective

OPE46-00040: QoL: Add batch kill operations

Add batch operations: monitor kill --pids 1234,5678,9012 and monitor kill --filter zombies to kill multiple processes at once.

MEASURED on origin/main: monitor kill <pid> (src/cli/index.ts:948) kills exactly one PID. Add batch selection: --pids 1234,5678 and --filter zombies (reuse the same filter vocabulary as monitor ps --filter: all|zombies|orphans|high_mem). Keep --dry-run working for the batch form and report a per-PID result.

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_f2853e86b557 · backend codewith · task 1e386b8d-7960-4bbd-a5a7-f67dfeabbfa4
🏭 Generated by @hasnaxyz/factory

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