refactor: P0-P3 fixes, C1 cleanup, architecture diagrams, go.work upgrade

- P0-1: ProviderError type + ReportStatus for precise 401/403 detection
- P0-2: Remove -config flag from deploy/homeagent.service
- P2-1: 5s debounce on context.go Save()
- P2-2→C1: Delete output_set_channel entirely
- P2-3: Extract mediaDataURL/mediaChat helpers
- P2-4: Dedup defaultSources var
- P3: Delete dead packages (embed/tokenizer/container/snapshot)
- P3: Delete dead functions (messagesToMap, RunStageAll)
- CL: Update .gitignore, docs, Makefile, gojieba removal
- Config: Delete config/config.yaml, update docs
- Arch: Remove EmitOutputTo from emitResponse
- CL-1: go.work 1.19→1.21
- Docs: Add Mermaid architecture diagrams to README
- Docs: Add kernel-rebuild requires plugin-rebuild note to PLUGIN_DEV.md

internal/plugins/agentcli/plugin.go

@@ -345,6 +345,10 @@ func (p *Plugin) handleCreate(s *sdk.PluginSDK, args map[string]interface{}) (in
 			timeout = d
 		}
 	}
+	// SSH 命令自动使用更长的超时（5 分钟）
+	if timeoutStr == "" && (strings.HasPrefix(command, "ssh ") || strings.HasPrefix(command, "ssh -")) {
+		timeout = 5 * time.Minute
+	}
 
 	rows := uint16(24)
 	cols := uint16(80)