prometeu-studio/docs/studio/pull-requests/PR-05a-assets-workspace-foundation-and-service-state.md

PR-05a Assets Workspace Foundation and Service State

Briefing

Implement the first executable slice of the Assets workspace based on:

• ../specs/4. Assets Workspace Specification.md

This PR creates the workspace foundation, service-facing state model, and event wiring required by all later Assets workspace slices.

Objective

Replace the current WorkspaceId.ASSETS placeholder with a concrete AssetsWorkspace foundation that can:

• boot inside the Studio shell,
• request and refresh asset data from Studio-facing services,
• maintain stable selection state,
• surface loading/empty/error states,
• and expose internal state in a way that later UI slices can reuse.

Dependencies

• existing Studio shell and event bus foundations
• existing packer-facing Studio contracts and specifications

Scope

• create a concrete AssetsWorkspace
• define workspace-local view state models for:
  • navigator state
  • selected asset state
  • loading/error state
• define service-facing DTO adapters needed by the workspace
• define workspace event publications for asset refresh and selection updates
• integrate the workspace into the existing shell/workspace switch flow

Non-Goals

• no final asset navigator visuals yet
• no final preview rendering yet
• no final staged mutation UI yet
• no production-grade packer backend implementation if stubs or adapters are still required

Execution Method

1. Replace the placeholder assets workspace with a concrete class and root layout.
2. Introduce workspace-local state objects for navigator, selection, and detail hydration.
3. Introduce a Studio-facing service boundary for loading asset collections and selected-asset details.
4. Wire the workspace into StudioWorkspaceEventBus for refresh and selection lifecycle.
5. Define stable loading, empty, no-results, and error states in code.

Acceptance Criteria

• selecting Assets opens a real workspace rather than a placeholder
• the workspace can request asset data through a Studio service boundary
• loading, empty, and error states are visible and distinct
• selection state is modelled explicitly and can be preserved by identity
• the workspace has enough state structure to support the later navigator and details PRs without redesign

Validation

• unit tests for workspace state transitions
• unit tests for selection retention logic
• UI smoke validation that the Assets workspace mounts cleanly in the shell

Affected Artifacts

• prometeu-studio workspace classes
• Studio event wiring
• Studio-facing asset service abstractions
• tests for workspace state and selection behavior