fix(cli): print usable Jupyter entry URL

[eetoc]

Summary

• print the Jupyter token-redirect entry when a run enables Jupyter without exposing its tokenized notebook URL
• preserve the direct /lab?token=... URL when the daemon returns an exposed notebook URL
• keep the reported proxy path unchanged for JSON consumers
• add regression coverage for non-exposed, exposed, trailing-slash, and already-normalized paths

Verification

• go test ./cmd/agent-compose -run 'TestIntegrationCLIRun(JupyterWithoutExposePrintsTokenRedirectEntry|SendsJupyterExpose)|TestJupyterBrowserLocation' -count=1\n- go test ./cmd/agent-compose -count=1\n- task lint\n- real Docker sandbox: the non-exposed URL redirected to a tokenized JupyterLab URL and completed with HTTP 200\n- real Docker sandbox: the exposed tokenized URL opened JupyterLab directly with HTTP 200\n\n## Known environment failures\n\n- task test reached deploy/install_test.sh and failed an existing incomplete-rollback message assertion (recovery was incomplete)\n- the full Linux artifact build could not refresh runtime artifacts because Docker Hub timed out while fetching golang:1-alpine

[monkeyscan]

PR Title: fix(cli): print usable Jupyter entry URL

Commit: 6c5ee2d

本次变更在 cmd/agent-compose/cli_jupyter.go 中新增了 jupyterBrowserLocation 函数，用于决定 Jupyter 浏览器跳转的目标路径：当存在暴露模式下的 notebookURL 时直接使用；否则从 proxyPath 去掉 /lab 后缀，得到入口重定向路径。同时在 main_test.go 中补充了集成测试和单元测试，验证私有 Jupyter 模式（--jupyter 无 --jupyter-expose）会打印 token redirect entry 路径而非直接的 /lab 路径。

代码逻辑简洁，边界场景（尾部斜杠、根路径 /lab、已存在的 entry path、暴露模式 notebookURL）均有测试覆盖。resolveRunJupyterOutput 中 Path 字段保留原始 proxyPath，URL 字段使用新的入口路径，职责分离清晰。未发现有正确性、安全或回归风险。

[eetoc]

Manual verification completed with real Docker sandboxes:

• --jupyter: CLI printed the sandbox entry URL without /lab or a token; the entry returned HTTP 307 to the tokenized JupyterLab URL, which returned HTTP 200.
• --jupyter-expose: CLI printed the tokenized /lab URL directly, and it returned HTTP 200 with JupyterLab.

The test sandboxes remained running during browser verification.