Add chat and ambient envs for DAP

What does this MR do and why?

Add chat and ambient envs for DAP

In order to align with industry terms in v1 version of Flow Registry environments use following names:

1. chat - for chat based agentic interactions between a human and a model
2. chat-partial - for custom agents dedicated shortened flow configs for chat based interactions
3. ambient - for agentic features that runs in background and require non to minimal level of a human interaction

This change has been extracted from !205187 (closed) which tested integration with v1 of Flow Registry built at AI Gateway

References

1. Define available environment for Duo Agent Plat... (gitlab-org/modelops/applied-ml/code-suggestions/ai-assist#1351)
2. Prepare Flow Registry V1 release (gitlab-org/modelops/applied-ml/code-suggestions/ai-assist#1469 - closed)

Screenshots or screen recordings

new_envs_verification

Before	After

How to set up and validate locally

1. configure DAP for GDK https://gitlab.com/gitlab-org/gitlab-development-kit/-/blob/main/doc/howto/duo_agent_platform.md?ref_type=heads
2. enabled AI Catalog ::Feature.enabled?(:global_ai_catalog, User.first)
3. checkout AI Catalog changes(from !205187 (closed)) to enable v1 version in Rails git checkout mwaw/use_flow_registry_v1_version_in_ai_catalog -- ee/app/services/ai/catalog/execute_workflow_service.rb ee/lib/ai/catalog/duo_workflow_payload_builder/experimental.rb
4. Run an agent from AI Catalog

MR acceptance checklist

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