[DwC export]: Create `schemamapping` table (or extend `spquery`)

[grantfitzsimmons]

Goal

Create the schemamapping table (or extend spquery with equivalent fields) to distinguish schema mapping queries from standard user queries.

Background

The schemamapping record wraps an spquery and adds metadata (MappingType, Name) necessary to segregate mappings from standard queries in the UI. Implementation approach (new table vs. extending spquery) is at the development team's discretion.

Schema (if new table)

Field	Type	Notes
SchemaMappingID	Int (PK)	Auto-increment
QueryID	FK → spquery	One-to-one, Required
MappingType	Enum (Core, Extension)	Required
Name	VarChar	User-facing description
IsDefault	Boolean	Default false; system defaults are read-only

Acceptance Criteria

• Table (or spquery extension) created in migration.
• MappingType enforced as enum with only Core and Extension values.
• One-to-one relationship with spquery enforced.
• IsDefault = true records are read-only (cannot be edited or deleted via UI).
• ORM model created and registered.
• Standard spquery records (non-mapping queries) are unaffected.