## What changed
Add `include_environment_context_time`, enabled by default. Setting it to `false` omits `<current_date>` and `<timezone>` while retaining the rest of the environment context, and skips the clock read used to populate the date.
## Testing
Extend configuration, session context, and external time provider tests to cover enabled and disabled time fields, context updates across turns, and current-time reminder behavior.
GitOrigin-RevId: 5071ce1701c044b680624d0cdbba7e0bc2b5bbe6
## What changed
- Add an embedded `defaults.toml` and always install it as the lowest-precedence configuration layer when no packaged-defaults path is supplied.
- Keep packaged defaults out of config RPC layer and origin metadata.
- Report a user setting as overridden only when the effective layer has higher precedence, so clearing a setting can fall back to its packaged default without a false override.
## Testing
- Cover loading the packaged layer when other configuration files are absent.
- Cover config RPC filtering and clearing a user value that falls back to a packaged default.
GitOrigin-RevId: c1c0e1e681e4ac1be2602550972533443c5df51b
surajs-oai