design(projects): make the new-project composer clearly read as create

[johnpc]

Design-polish pass — driven by the LLM feedback panel (npm run panel, wedding scenario). The panelist's top complaint (delight 3/10): "Had to type 'Wedding' multiple times without clear feedback on whether it was creating or searching… no visual distinction between search, create, and navigation actions."

Looking at the flow, the cause is real: when the "New project" button expands into its composer, it drops the "+ New project" framing entirely — leaving a bare text input in a dashed box next to a generic "Add" button, which reads ambiguously like a search field.

Fix (CSS + a small markup tweak, tokens only)

• Kept a persistent "+" icon (accent-strong) at the start of the open composer, so it visually reads as a create action, not a search box.
• Clarified the placeholder: "Project name" → "Name your new project".

Now the composer unmistakably communicates "create a project" on both viewports.

Also in this PR — a panel-tool fix

The same panel run surfaced a bug in the harness itself: the Amazon Nova Pro panelist errored because amazon.nova-pro-v1:0 isn't callable on-demand. Corrected its model id to the inference-profile form us.amazon.nova-pro-v1:0 in scripts/llm-panel/scenarios.mjs, so all four panelists run.

Before → after

• Desktop: https://files.jpc.io/d/DPJRt-newproject-composer-desktop.png
• Mobile: https://files.jpc.io/d/WBf2H-newproject-composer-mobile.png

Full quality gate green; presentational + a scripts-only tool fix. Verified against the sandbox (AWS_PROFILE=personal).

Note: the panel's other ask — a success confirmation toast after creating — is a behavior change (new UI/state), outside this loop's visual-polish mandate, so it's logged as a backlog item rather than included here.