FIXED - Make adding a portfolio project simpler and actually saveable

- Fix critical bug: TabsContent unmounted inactive panels, so the project
  form only submitted the active tab's fields and could never save; add an
  opt-in forceMount that keeps panels mounted (hidden) and use it on all
  four project-form tabs
- Make Sections and Assets optional: a project saves with just Basics and
  Localized Content; new projects start with no sections/assets, and the
  last one can now be removed
- Update wizard progress so empty sections/assets steps count as complete
- Update save hint copy and step labels to reflect the optional steps
- Correct .claude/launch.json dev port to 3014
- Update portfolio-form-progress tests for the optional-steps behaviour

lib/portfolio-form-progress.ts

@@ -136,13 +136,21 @@ export function getPortfolioWizardProgress(
     },
     {
       key: "sections",
-      complete: input.sections.length > 0 && completedSections === input.sections.length,
-      summary: `${completedSections}/${input.sections.length} sections ready.`,
+      // Optional: no sections is valid. If sections were added, each must be ready.
+      complete: completedSections === input.sections.length,
+      summary:
+        input.sections.length === 0
+          ? "Optional — no sections added."
+          : `${completedSections}/${input.sections.length} sections ready.`,
     },
     {
       key: "assets",
-      complete: input.assets.length > 0 && completedAssets === input.assets.length,
-      summary: `${completedAssets}/${input.assets.length} assets ready.`,
+      // Optional: no gallery assets is valid. If assets were added, each must be ready.
+      complete: completedAssets === input.assets.length,
+      summary:
+        input.assets.length === 0
+          ? "Optional — no gallery assets added."
+          : `${completedAssets}/${input.assets.length} assets ready.`,
     },
   ];
 }