Rename user-facing "AI Bridge" strings to "AI Gateway" in deployment
config, RBAC display names, log messages, error strings, docs style
guide, and Grafana dashboard README.
Deprecated option names and descriptions (the `--aibridge-*` block) are
intentionally kept as "AI Bridge". The `Name` field cannot be renamed
because `serpent` uses it as a unique key during JSON serialization;
duplicating names causes `UnmarshalJSON` failures (e.g. in the support
bundle). Descriptions also stay as "AI Bridge" to avoid confusion
between the deprecated and primary options.
Refs https://linear.app/codercom/issue/AIGOV-226
> Generated with the assistance of Coder Agents (@ssncferreira)
Susana Ferreira
56373a09fc