Remove ZeroShot related classes

.gitlab/ci/rails.gitlab-ci.yml

.rubocop_todo/layout/class_structure.yml

.rubocop_todo/rspec/be_eq.yml

.rubocop_todo/rspec/named_subject.yml

doc/development/ai_features/duo_chat.md

doc/development/ai_features/logged_events.md

ee/app/models/ai/ai_resource/ci/build.rb

ee/app/models/ai/ai_resource/commit.rb

ee/app/models/ai/ai_resource/epic.rb

ee/app/models/ai/ai_resource/issue.rb

ee/app/models/ai/ai_resource/merge_request.rb

ee/lib/gitlab/llm/chain/agents/zero_shot/executor.rb

...ib/gitlab/llm/chain/agents/zero_shot/prompts/anthropic.rb

ee/lib/gitlab/llm/chain/agents/zero_shot/prompts/base.rb

ee/lib/gitlab/llm/chain/gitlab_context.rb

ee/lib/gitlab/llm/chain/streamed_zero_shot_answer.rb

ee/lib/gitlab/llm/chain/tool_response_modifier.rb

ee/lib/gitlab/llm/chain/utils/prompt.rb

...ec/lib/gitlab/llm/chain/agents/zero_shot/executor_spec.rb

...tlab/llm/chain/agents/zero_shot/prompts/anthropic_spec.rb