feat(kimi-code): support Kimi Computer Use on Windows

[wbxl2000]

Related Issue

No linked issue. The official Windows x64 Kimi Computer Use plugin and runtime are available, but the built-in CLI capability was still limited to macOS.

Problem

Windows users could not discover or install Kimi Computer Use from the Official tab. The capability also needs to distinguish its stable product ID from the platform-specific backing plugin ID so installation, updates, removal guidance, and marketplace counts stay consistent.

What changed

• Keep one kimi-cu capability while selecting the macOS or Windows x64 backing plugin and runtime flow by platform.
• Reuse plugin installation and MCP enablement across platforms; on Windows, run the official signed runtime setup through the absolute system PowerShell path and verify the result with doctor.
• Map the Windows backing plugin to the built-in capability for installed status, update actions, removal guidance, logs, and official-source labeling.
• Document Windows x64 availability and add a minor CLI changeset.

Validation

• pnpm --filter @moonshot-ai/agent-core-v2 exec vitest run test/app/capability/kimiCu.test.ts (26 tests)
• pnpm --filter @moonshot-ai/kimi-code exec vitest run test/tui/components/dialogs/plugins-selector.test.ts test/tui/commands/plugins-capability.test.ts (53 tests)
• pnpm --filter @moonshot-ai/agent-core-v2 lint:imports
• pnpm --filter @moonshot-ai/agent-core-v2 typecheck
• pnpm --filter @moonshot-ai/kimi-code typecheck
• pnpm --filter @moonshot-ai/klient typecheck
• pnpm -C docs run build
• Targeted type-aware oxlint, git diff --check, and pnpm changeset status --since=origin/main

The package-wide agent-core-v2 test script was also attempted, but the local run hit EMFILE: too many open files in unrelated file-watcher and plugin-manager tests; the focused capability suite above passed.

Checklist

• I have read the CONTRIBUTING document.
• I have linked a related issue, or explained the problem above.
• I have added tests that prove my feature works.
• Ran gen-changesets skill, or this PR needs no changeset.
• Ran gen-docs skill, or this PR needs no doc update.

[pkg-pr-new]

pnpm dlx https://pkg.pr.new/@moonshot-ai/kimi-code@4ff18d0

npx https://pkg.pr.new/@moonshot-ai/kimi-code@4ff18d0

commit: 4ff18d0