chore(release): prepare @letra-ai/cli 0.6.1

[jspengine]

Release preparation

Prepares @letra-ai/cli 0.6.1 for a new release tag while preserving the existing v0.6.0 tag.

• Fixes the Kanban task progress type error that blocked the previous publish workflow.
• Removes internal @letra/types from runtime dependencies.
• Restricts the package contents to dist and declares Node.js 22+.
• Adds a clean consumer smoke test covering CLI, workspace initialization, harness, API and web assets.
• Runs the smoke test in CI before any npm publish and verifies the tag matches the package version.

Validation

• npm run build passed.
• npm run typecheck passed.
• npm run test:package -- --pack-destination .tmp/release-0.6.1-final passed.
• npm run test:client has 4 pre-existing WorkspacesView assertion failures (Novo workspace vs Novo Workspace).
• npm test and repository lint have pre-existing failures documented in the canonical release validation report.

The npm publication remains gated by this PR and a future v0.6.1 tag.