Macro declaration models are reachable only by numbered names (MacroDeclaration15, MacroDeclaration16, asset_union.MacroDeclaration6) #1783

A seller that validates or builds an asset's macro_declarations has to pick the generated model for that asset. Today the only names are codegen counters. On 10.0.0b4:

• display_tag_asset has MacroDeclaration (tag URL: location.field is Literal['url']), MacroDeclaration15 (inline markup: Literal['markup']) and MacroDeclaration16 (paired redirect: ad_request_url / clickthrough_url);
• asset_union has MacroDeclaration through MacroDeclaration10 plus MacroDeclarationModel.

The numbers move when the bundle changes. On 9.3.0 the three display-tag variants shared one location type. AdCP 3.3 gave each delivery its own fields, so the same import now validates different things. Code written against MacroDeclaration for a paired redirect started refusing clickthrough_url on 10.0.0b2 with no rename to signal it.

Example

The Scope3 embedded sales agent's test factory (tests/factories/macro_declaration.py) builds declarations for each display_tag delivery and has to import:

from adcp.types.domains.core.assets.asset_union import MacroDeclaration6
from adcp.types.domains.core.assets.display_tag_asset import MacroDeclaration as TagUrlMacroDeclaration
from adcp.types.domains.core.assets.display_tag_asset import MacroDeclaration15 as InlineMarkupMacroDeclaration
from adcp.types.domains.core.assets.display_tag_asset import MacroDeclaration16 as PairedRedirectMacroDeclaration

On 10.0.0b4:

from adcp.types.domains.core.assets.display_tag_asset import MacroDeclaration
MacroDeclaration.model_validate({..., "location": {"field": "clickthrough_url", "occurrence": 0, "context": "url_query_value"}})
# ValidationError: location.field Input should be 'url'

Suggested fix

Emit stable, meaningful names for these variants: per delivery_type for display_tag (TagUrlMacroDeclaration, InlineMarkupMacroDeclaration, PairedRedirectMacroDeclaration) and per asset type in asset_union, or a title-derived name from the schema. Export them from adcp.types, as #1360 did for other generated classes. A helper such as macro_declaration_model(asset_type, delivery_type) would also work.