fix(dashboard): allow adding metadata when all rows are non-primitive

[Kavin-Bakyaraj]

What

Adds a standalone "Add row" action to the metadata form, so metadata can still be added when every existing row holds a non-primitive value.

Closes #16287

Why

Row insertion is only reachable through each row's dropdown menu, and that menu is hidden for rows holding non-primitive values (hidden: isDisabled on DropdownMenu.Trigger).

When every metadata entry is an object or an array, every row is disabled, so no dropdown renders anywhere and no insertion point is left. For a product category whose only metadata is:

{
  "category_image": {
    "id": "file_123",
    "url": "https://example.com/category.jpg"
  }
}

the editor is effectively read-only, and the author cannot add a primitive key without going through the API.

How

• addRow appends a blank editable row through useFieldArray's append, independent of any row's disabled state.
• The action renders below the table as a secondary button, following the add-item pattern already used in manage-variant-inventory-items-form.
• Non-primitive rows are untouched: they stay disabled and read-only, and parseValues still passes their original values through unchanged.

Two notes on the choices here:

• I kept the existing protection on non-primitive rows rather than making them deletable, which was floated in the issue thread. Allowing deletion changes what an author can do to data the form cannot display, which feels like a separate product decision from restoring the ability to add a row. Happy to follow up in that direction if you'd prefer it.
• The action is always visible rather than appearing only when all rows are disabled. The hover-only dropdown is not very discoverable, and gating the control would make "can I add metadata here?" depend on the shape of the existing data.

metadata.edit.actions.addRow was added to en.json and to $schema.json, including its required list, which the existing validate-translations spec enforces.

Testing

Added metadata-form.spec.tsx covering:

• the add row action is present when the only row is non-primitive, and that row is disabled
• using it appends an editable row
• submitting an added key sends it alongside the preserved non-primitive value
• the action stays available for ordinary editable metadata

All four fail on develop and pass with this change (verified by reverting only metadata-form.tsx).

yarn workspace @medusajs/dashboard test
# 15 files, 111 tests passing

ESLint and Prettier are clean on the touched files.

[changeset-bot]

🦋 Changeset detected

Latest commit: 2adf08f

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 79 packages

Name	Type
@medusajs/dashboard	Patch
@medusajs/draft-order	Patch
@medusajs/loyalty-plugin	Patch
@medusajs/admin-bundler	Patch
@medusajs/medusa	Patch
@medusajs/test-utils	Patch
@medusajs/medusa-oas-cli	Patch
integration-tests-http	Patch
@medusajs/analytics	Patch
@medusajs/api-key	Patch
@medusajs/auth	Patch
@medusajs/caching	Patch
@medusajs/cart	Patch
@medusajs/currency	Patch
@medusajs/customer	Patch
@medusajs/file	Patch
@medusajs/fulfillment	Patch
@medusajs/index	Patch
@medusajs/inventory	Patch
@medusajs/link-modules	Patch
@medusajs/locking	Patch
@medusajs/notification	Patch
@medusajs/order	Patch
@medusajs/payment	Patch
@medusajs/pricing	Patch
@medusajs/product	Patch
@medusajs/promotion	Patch
@medusajs/rbac	Patch
@medusajs/region	Patch
@medusajs/sales-channel	Patch
@medusajs/settings	Patch
@medusajs/stock-location	Patch
@medusajs/store	Patch
@medusajs/tax	Patch
@medusajs/translation	Patch
@medusajs/user	Patch
@medusajs/workflow-engine-inmemory	Patch
@medusajs/workflow-engine-redis	Patch
@medusajs/oas-github-ci	Patch
@medusajs/cache-inmemory	Patch
@medusajs/cache-redis	Patch
@medusajs/event-bus-local	Patch
@medusajs/event-bus-redis	Patch
@medusajs/analytics-local	Patch
@medusajs/analytics-posthog	Patch
@medusajs/auth-emailpass	Patch
@medusajs/auth-github	Patch
@medusajs/auth-google	Patch
@medusajs/caching-redis	Patch
@medusajs/file-local	Patch
@medusajs/file-s3	Patch
@medusajs/fulfillment-manual	Patch
@medusajs/locking-postgres	Patch
@medusajs/locking-redis	Patch
@medusajs/notification-local	Patch
@medusajs/notification-sendgrid	Patch
@medusajs/payment-stripe	Patch
@medusajs/core-flows	Patch
@medusajs/framework	Patch
@medusajs/js-sdk	Patch
@medusajs/modules-sdk	Patch
@medusajs/orchestration	Patch
@medusajs/query	Patch
@medusajs/types	Patch
@medusajs/utils	Patch
@medusajs/workflows-sdk	Patch
@medusajs/http-types-generator	Patch
@medusajs/cli	Patch
@medusajs/deps	Patch
@medusajs/eslint-plugin	Patch
@medusajs/telemetry	Patch
@medusajs/admin-sdk	Patch
@medusajs/admin-shared	Patch
@medusajs/admin-vite-plugin	Patch
@medusajs/icons	Patch
@medusajs/toolbox	Patch
@medusajs/ui-preset	Patch
create-medusa-app	Patch
@medusajs/ui	Patch

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[medusa-os-bot]

Thanks for the contribution! Initial automated review looks good.

Adds a standalone "Add row" button to the metadata form so authors can insert new primitive rows when every existing row holds a non-primitive value and the per-row dropdown is hidden. Template complete, linked to verified issue #16287, changeset present with correct patch bump, four targeted tests pass. No security, performance, or correctness issues found. Heads up: PR #16288 also references issue #16287 and was opened earlier; if #16288 is merged first, this PR may be closed as a duplicate.

Triggered by: new PR opened