feat(agents-api): New chat context query and model

[creatorrr]

• feat(typespec): Add initial typespec definitions
• feat(typespec): Add Tasks typespec
• feat(typespec): Add Executions typespec
• feat: Add session token budget and context overflow
• fix(typespec): Minor spec fixes
• feat(typespec): Add name field to Tool
• refactor(typespec): Minor refactors to common/ utils
• feat(typespec): Add search endpoints
• feat(typespec): Add multi-agent multi-user sessions, add template for situation
• refactor: Remove mock_openapi.yaml and link openapi.yaml to the typespec generated file
• feat: Codegen for all new typespec stuff
• feat(fern): Upgrade fern and fern-python
• feat(typespec): Various changes to the spec
• fix(typespec): Fix docstrings
• wip
• wip
• fix(agents-api): Fix datamodel-codegen options
• fix(typespec): Misc fixes
• feat(agents-api): Add migrations for updated typespec models
• wip
• wip
• feat(agents-api): Add migrations for developers relations and renaming information_snippets
• wip
• wip
• wip
• fix(agents-api): Update agent/tool models
• wip
• wip
• wip
• wip
• wip
• wip
• wip
• reformat evthing
• wip
• wip
• wup
• history
• feat(agents-api): New chat context query and model