[Core]: Formal identity type-plugin bind via TypeRegistry`

[rosspeili]

Component

agent registry / identity

Kind

enhancement

Description

#55 resolves operator identity via OperatorIdentityAdapter at session open. Align with type-plugin.contract.md:

• Register identity plugins on TypeRegistry with role: identity
• bind() returns capabilities; emit type.bound / type.unbound alongside identity.bound
• Profile types[] entries drive adapter selection without ad hoc config keys
• Community adapters use custom.* namespace

Code or session context (optional)

aura/core/registry.py, aura/identity/bind.py, spec/type-plugin.contract.md