Make model presets a single global collection and treat presets as reusable setups (main, utility, embedding). Persisted scope configs now store only a preset name (Default is always present and immutable); project-scoped preset definitions were removed and attempts to edit/reset project presets are rejected. Add embedding-model support throughout: include embedding slot in presets, surface embedding in the switcher and override APIs, and notify extensions when the effective embedding model changes. Implement rename/retire propagation to update plugin configs, saved chats, and live AgentContext objects when preset names change or presets are removed. Update CLI/integration commands to use an "inherit" action for returning to the scoped preset and to report the effective scoped-or-chat preset. Add startup migration/bootstrap to initialize presets from remote or bundled fallback and numerous docs/UI text updates to reflect the new preset model. Extra: refactor config resolution helpers and add safety checks (validation, atomic writes) when saving presets.
Repair saved _model_config user config and presets so Venice model slots use chat completions with the Venice system prompt disabled. Leave a0_venice slots untouched and add regression coverage for parsing and slot preservation.
- Change @extensible decorator to generate extension paths from full module and qualname hierarchies instead of flattened names
- Update extension path format from `{module}_{qualname}_{start|end}` to `_functions/<module>/<qualname>/{start|end}`
- Move all extension files to new deep directory structure under `_functions/` to match new path format
- Replace PathSpec.from_lines(GitWildMatchPattern, ...) with PathSpec.from_lines
