support dynamic types for cells

Author: Templarian

src/components/pg/table/README.md

@@ -75,6 +75,7 @@ The `createTableItem` unrolls the `{ key: value }` shorthand to `items: [{ key,
 
 - Primitive values pick the default cell by type: `string`, `number`, or `boolean`.
 - Object values are spread onto the cell as props and must include a `type` cell component (e.g. `{ type, icon, value }`). A `key` field inside the object is ignored; the shorthand key wins.
+- `type` may also be a factory `(item) => CellComponent` that picks the cell editor from the item's data (e.g. `{ type: (item) => item.value < 0 ? PgTableCellText : PgTableCellNumber, value: 42 }`). Returning `null`/`undefined` falls back to the default cell for the value type.
 - `null`/`undefined` values have no default cell and throw; use an object value with an explicit `type`.
 
 ```typescript

src/components/pg/tableRow/README.md

@@ -2,7 +2,7 @@
 
 See `PgTable`. Internal row component; created by `PgTable` from `data` items.
 
-Renders a cell per item, picking the component from the item `type` or defaulting by `typeof item.value` (`string` → `PgTableCellText`, `number` → `PgTableCellNumber`, `boolean` → `PgTableCellCheck`). Re-dispatches cell `action` events with `index`, `key`, `getColumn`, `getRow`, and `getRows` added to the detail.
+Renders a cell per item, picking the component from the item `type` — a cell component class or a factory `(item) => CellComponent` — or defaulting by `typeof item.value` (`string` → `PgTableCellText`, `number` → `PgTableCellNumber`, `boolean` → `PgTableCellCheck`). Re-dispatches cell `action` events with `index`, `key`, `getColumn`, `getRow`, and `getRows` added to the detail.
 
 | Attributes | Tested   | Default | Description |
 | ---------- | -------- | ------- | ----------- |

src/components/pg/tableRow/tableRow.ts

@@ -37,7 +37,12 @@ export default class PgTableRow extends HTMLElement {
       container: this.$cells,
       items: this.items,
       type: (item) => {
-        const type = item.type ?? types.get(typeof item.value);
+        let type = item.type;
+        if (typeof type === 'function' && !(type.prototype instanceof HTMLElement)) {
+          // factory form: (item) => cell component class
+          type = type(item);
+        }
+        type ??= types.get(typeof item.value);
         if (!type) {
           throw new Error(`no cell component for key '${item.key}'; use a string, number, or boolean value, or set an explicit 'type'`);
         }