Offer supply suggestions, drop the circuit column, center cells

The Versorgung field suggests ELT and MSR (plus values already used in
the balance) through a datalist and still accepts free text. The circuit
number column is not needed in early design phases; it is removed from
the data model, the regenerated migration 0010, the editor and the
print. All cells are centered except "Verbraucher / Flächen", group
titles and total labels.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/db/schema/estimate-balances.ts

@@ -44,7 +44,6 @@ export const estimateRows = sqliteTable(
       .references(() => estimateGroups.id, { onDelete: "cascade" }),
     sortOrder: integer("sort_order").notNull().default(0),
     supply: text("supply"),
-    circuitRef: text("circuit_ref"),
     name: text("name").notNull().default(""),
     quantity: real("quantity").notNull().default(0),
     unit: text("unit", { enum: ["piece", "area"] }).notNull().default("piece"),