Add an artifact dock and runtime log console

[KSemenenko]

Problem

The operator workbench needs one place to inspect attached files, generated artifacts, runtime logs, and task output.

Scope

• Track the artifact dock, attachment previews, runtime logs, and session output console
• Define how artifacts and logs relate to the current session and selected workspace

Out of scope

• Telemetry dashboards beyond the workbench-level console needs
• Provider setup screens that belong in the Toolchain Center

Implementation notes

• Keep artifacts and logs inspectable without leaving the main workbench
• Align this issue with session replay and tool-call audit requirements
• Support coding and non-coding sessions equally

Definition of Done

• The issue defines the minimum artifact and console surfaces the workbench must expose
• The relationship between session context and artifact visibility is explicit

Verification

• Review the issue against the feature spec attachment and inspection flows

Dependencies

• Parent epic: [Epic] Replace the static prototype with a real desktop workbench #13
• Depends on: Implement session persistence, replay, checkpointing, and resume