fix(cli): keep image command tree supported

[fuchencong]

Summary

• keep agent-compose image and its ls, pull, build, rm, and inspect subcommands as supported CLI commands without deprecation warnings
• make agent-compose image pull [image] match the top-level pull [image] shortcut, including the no-argument project image workflow
• update CLI regression coverage, README, and the English and Chinese command-line manuals to document the image command tree and its top-level shortcuts

Testing

• GOFLAGS=-buildvcs=false go test ./cmd/agent-compose -run 'TestCLIImageRootCommandShowsHelp|TestIntegrationCLIImagesAliasesAndJSON|TestIntegrationCLIImagePullAliasesAndJSON|TestIntegrationCLIPullProjectImages|TestIntegrationCLIProjectBuildImages|TestIntegrationCLIImageRemoveAliasesAndJSON|TestIntegrationCLIImageInspectJSON|TestE2ECLIHelpCommands' -count=1
• GOFLAGS=-buildvcs=false task lint GO_BUILD_CACHE_DIR="$GOCACHE" GOLANGCI_LINT_CACHE_DIR="$GOLANGCI_LINT_CACHE"
• GOFLAGS=-buildvcs=false task build GO_BUILD_CACHE_DIR="$GOCACHE"
• task test GO_BUILD_CACHE_DIR="$GOCACHE"
  • Unit: 74.17%
  • Integration: 62.53%
  • E2E: 61.75%
  • Combined: 78.08%
• task docs:build currently fails because the existing English agent-compose-yaml-manual.md does not reference the commit, description, and display_name schema fields; this PR does not modify that manual or those schema fields

Checklist

• Documentation updated when behavior or configuration changed.
• Tests added or updated for user-visible behavior.
• No secrets, private endpoints, internal certificates, or local runtime state included.

[monkeyscan]

PR Title: fix(cli): keep image command tree supported

Commit: 93d23bc

本次 PR 将 agent-compose image 子命令树从“已废弃”状态提升为正式支持的命令结构，同时保留顶层快捷命令（如 pull、images、build、rmi、inspect image）作为别名。

核心改动：

1. cmd/agent-compose/main.go：移除了 image、image ls、image pull、image build、image rm、image inspect 上的废弃警告逻辑；将 image pull 的参数约束从 ExactArgs(1) 改为 RangeArgs(0, 1)，并让其统一委托给 runComposePullCommand，从而支持无参数时拉取整个项目的镜像（与顶层 pull 行为对齐）。
2. cmd/agent-compose/main_test.go：移除了废弃警告的断言；在 TestIntegrationCLIPullProjectImages 中新增了对 image pull（无参数）的测试覆盖，验证顶层命令与 image 子命令行为一致。
3. cmd/agent-compose/cli_help_e2e_test.go：更新了 help 文本期望，要求 stderr 为空（不再允许废弃警告），并新增了 image pull --help 的覆盖。
4. docs / README：将文档中的命令示例从顶层快捷命令更新为 image 子命令形式，并明确列出顶层快捷命令与 image 子命令的对应关系。

整体评估：变更逻辑清晰，测试覆盖充分，文档同步更新，没有发现引入正确性、安全性或兼容性风险的缺陷。

[innomentats]

LGTM