[BUG] Desktop app, third-party (gateway) mode: Ultracode never appears in the Code tab effort slider because the public model catalog has no ultracode effort option

Environment

• Claude desktop app 2.19675.0, macOS 26.6.2 (arm64), Code tab, local session
• Bundled Claude Code 2.1.286
• Third-party inference mode (inferenceProvider: "gateway", static credential), model claude-opus-5-5
• Dynamic workflows: enabled in the app Settings page

What happens

The effort slider in the Code tab composer offers Low, Medium, High, Extra high and Max. There is no Ultracode item, for any model. Turning on Dynamic workflows in Settings does not change this.

The standalone CLI on the same machine shows Ultracode in /effort, and the Workflow tool and the ultracode keyword work inside the desktop sessions. So workflows are available; only the slider item is missing.

Expected

The slider offers Ultracode, as it does in first-party mode ("Added Ultracode to the effort slider" in the app changelog).

Cause (from the shipped renderer bundle)

• The composer slider does not add the Ultracode item itself. The effort-option filter keeps an option whose id is ultracode only when ultracodeAvailable is true, and otherwise passes the catalog options through. So the item appears only when the model catalog already contains an ultracode effort option.
• In third-party mode the app uses the public model catalog (https://downloads.claude.ai/model-catalog/v1/catalog.json). Its ccd surface lists only low, medium, high, xhigh, max in thinking.effort_options for every model (the cached copy has no ultracode entry anywhere).
• The other gates appear to pass: the model offers xhigh, disableWorkflows is not set, the session transport supports applyFlagSettings, and the claude_code_workflows feature falls back to available because the third-party feature map leaves it undefined.

Result: in third-party mode the Ultracode slider item can never appear.

Suggested fix

Either add an ultracode effort option to the ccd surface of the public catalog for models that support it, or let the renderer insert the Ultracode item when ultracodeAvailable is true and the model offers xhigh, instead of relying on the catalog.