fix(smb): close smb sessions during transfers

[shoyuf]

Summary / 摘要

Fix SMB session lifecycle handling during long transfers.

• Store the *smb2.Session in the SMB driver so cleanup can call Session.Logoff(), not only Share.Umount().

• Add connection leases around SMB operations so idle refresh does not replace a session while a file stream, upload, or same-storage copy is still active.

• Keep the SMB download lease alive until the returned Link stream is closed.

• Log off partially initialized sessions if Mount fails after Dial succeeds.

• This PR has breaking changes.

• This PR changes public API, config, storage format, or migration behavior.

• This PR requires corresponding changes in related repositories.

Related repository PRs:

• OpenList-Frontend:
• OpenList-Docs:

Related Issues / 关联 Issue

Fixes #2578
Related to #2228

Testing / 测试

• gofmt drivers/smb/driver.go drivers/smb/util.go
• GOCACHE=/private/tmp/openlist-go-build-cache GOMODCACHE=/private/tmp/openlist-go-mod-cache GOPROXY=https://goproxy.cn,direct go test ./drivers/smb
• go test ./...
• Manual test / 手动测试:

go test ./... was attempted, but unrelated existing packages fail:

• multiple drivers/offline packages fail on Go vet non-constant format string diagnostics;
• pkg/aria2/rpc expects a local aria2 RPC server at localhost:6800.

The SMB package itself compiles successfully.

Checklist / 检查清单

• I have read CONTRIBUTING.
• I confirm this contribution follows the repository license, contribution policy, and code of conduct.
• I have formatted the changed code with gofmt.
• I have requested review from relevant maintainers or code owners where applicable.

AI Disclosure / AI 使用声明

• This PR includes AI-assisted content.

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• Gemini
• Other:

Usage scope / 使用范围:

• Code generation / 代码生成

• Refactoring / 重构

• Documentation / 文档

• Tests / 测试

• Review assistance / 审查辅助

• I have reviewed and validated all AI-assisted content included in this PR.

• I have ensured that all AI-assisted commits include Co-Authored-By attribution.

• I can reproduce all AI-assisted content included in this PR without any AI tools.

[xrgzs]

Don't commit this file.

[shoyuf]

Don't commit this file.

sorry, I forgot this