New categories saved but rendered nowhere

[brianorwhatever]

Adding a category looked like it silently failed. It didn't — it saved and then rendered nowhere.

Verified against prod before changing anything: the list already had both categories stored.

itemCategories: 18 saved
    🥬 Produce …
    🏷️ Food (id=food)      ← added, never displayed
    🏷️ test (id=test)      ← added, never displayed
    🛒 Other (id=other)

Cause

groupByCategory dropped every category with no items. That was right while categories were implicit — a five-item grocery list shouldn't be buried under 15 unused aisle headers — and wrong the moment users create categories by hand. It also left no drop target: you can't drag an item into a category that isn't rendered, so a new category could never receive its first item.

Fix

Visibility keys off a new isPristineDefault: an empty category is hidden only when it's a built-in the user has never touched.

Category	Empty	Shown
Untouched built-in (Bakery)	yes	no — keeps short lists clean
User-added (Luggage)	yes	yes
Renamed built-in (Produce → Fruit)	yes	yes — renaming signals intent
Re-emoji'd built-in	yes	yes
Other	yes	no — noise until something lands in it

On how this shipped

The old behaviour had a passing test asserting it ("groupByCategory omits empty categories, including Other"). It encoded the previous assumption rather than the requirement, so it locked in the bug instead of catching it. Replaced with cases for an added category, a renamed built-in, and a re-emoji'd built-in.

151 pass / 0 fail. Both typechecks clean; lint unchanged.

After merge

Wait for Railway, then reload — "Food" and "test" are already in your list and will simply appear. Nothing to re-create.

🤖 Generated with Claude Code

Note

Show empty user-created and modified categories that were previously hidden

• groupByCategory in categories.ts previously hid all empty categories; it now hides only empty built-in categories that are untouched (same name and emoji as the default).
• A new isPristineDefault predicate in itemCategories.ts checks whether a category matches its original built-in definition by id, name, and emoji.
• User-created categories and renamed or re-emoji'd built-ins are now included in grouped results with an empty items array when they have no items.
• Behavioral Change: empty categories that were previously omitted from results will now appear if the user created or modified them.

^{Macroscope summarized c62f59d.}