build: harden workspace manifest entrypoints

[nike-beep]

Summary

• add a root test:coverage manifest entrypoint
• add test:coverage scripts to @wanman/cli, @wanman/finops, @wanman/host-sdk, and @wanman/runtime
• replace POSIX-only rm -rf clean commands in the root, CLI, FinOps, host SDK, and runtime manifests with Node fs.rmSync commands that work on Windows and POSIX hosts

Verification

• [pass] pnpm --dir packages/cli run clean
• [pass] pnpm --dir packages/runtime run clean
• [pass] pnpm --dir packages/host-sdk run clean
• [pass] pnpm --dir packages/finops run clean
• [pass] node --input-type=module -e "import { rmSync } from 'node:fs'; rmSync('node_modules', { recursive: true, force: true });" in a temporary directory to verify the root cleanup path on Windows
• [fail, pre-existing] corepack pnpm run test:coverage
  Current failures remain in existing CLI/runtime suites (packages/cli/src/commands/takeover.test.ts, packages/cli/src/local-supervisor.test.ts, packages/cli/src/execution-session.test.ts, packages/runtime/src/__tests__/credential-manager.test.ts, packages/runtime/src/__tests__/codex-adapter.test.ts, packages/runtime/src/__tests__/agent-process.test.ts, packages/runtime/src/__tests__/config.test.ts, packages/runtime/src/__tests__/brain-integration.test.ts, packages/runtime/src/__tests__/merge-queue.test.ts, packages/runtime/src/__tests__/supervisor-git.test.ts, packages/runtime/src/__tests__/worktree-manager.test.ts) and were reproduced without touching executable source files in this PR.

Coverage Notes

• This PR only changes package manifests; no executable source files were modified.
• The manifest entrypoint work now covers both test/coverage and clean commands so Windows hosts do not need a POSIX shell for documented cleanup paths.
• Detailed failure notes are recorded in C:\Users\52895\Documents\wanman 2\.wanman\agents\devops\output\devops-notes.md.

Tasks: bb9a1089, f0e09187
Capsule: 0022c635