fix: Add missing impressions and paused fields to package request schemas

[BaiyuScope3]

Problem

Schema inconsistency report identified that core/package.json defines fields that cannot be set when creating or updating packages:

Field	core/package.json	package-request.json	update-media-buy-request.json
impressions	✅ Defined	❌ Missing	❌ Missing
paused	✅ Defined (default: false)	❌ Missing	✅ Present

This made it impossible for buyers to:

• Set impression goals when creating or updating packages
• Create packages in a paused state (e.g., for setup-then-activate workflows)

Solution

Added the missing fields to the request schemas:

package-request.json:

• Added impressions (number, optional) - Impression goal for the package
• Added paused (boolean, optional, default: false) - Create package in paused state

update-media-buy-request.json:

• Added impressions (number, optional) - Update impression goal for the package

Why add impressions?

Buyers need to specify delivery goals. The impressions field was defined in the entity schema but unreachable via API, making impression-based campaign planning impossible.

Why add paused to creation?

Common use cases require creating packages in a paused state:

• Setup-then-activate workflows - Create everything, review, then manually activate
• Multi-package coordination - Create all packages paused, then activate together
• Approval workflows - Create in draft/paused state pending approval
• Testing/Staging - Verify setup before going live

Since update_media_buy already supports paused, it makes sense for create_media_buy to support it too—avoiding the need for an immediate follow-up API call.

Why NOT change format_ids vs format_ids_to_provide?

We evaluated the naming inconsistency between:

• format_ids (in package-request.json) - buyer's selection
• format_ids_to_provide (in core/package.json) - publisher's confirmation

Decision: Keep as-is. This is intentional design:

1. Different semantics - Request = "I want these formats" → Response = "Provide creatives for these formats"
2. Avoiding breaking change - Renaming would require field deprecation cycle, which contains more efforts for now, let's leave it as it is.
3. Instructive naming - format_ids_to_provide clearly communicates "action required" to the buyer

Changes

• static/schemas/source/media-buy/package-request.json - Added impressions and paused
• static/schemas/source/media-buy/update-media-buy-request.json - Added impressions
• docs/media-buy/task-reference/create_media_buy.mdx - Updated parameter table
• docs/media-buy/task-reference/update_media_buy.mdx - Updated parameter table
• .changeset/fix-package-request-fields.md - Changeset for release notes
• Fixed missing @jest/test-sequencer dev dependency

Testing

All existing tests pass:

• ✅ Schema validation
• ✅ Example validation
• ✅ Extension fields
• ✅ JSON schema validation
• ✅ Composed schema validation
• ✅ Migration validation
• ✅ Unit tests