Rebase PR #2282 onto main (post-#2332) and unify feature flag
allowlists into a single source of truth.
- Add MCPAppsFeatureFlag, AllowedFeatureFlags, InsidersFeatureFlags,
and ResolveFeatureFlags in feature_flags.go
- AllowedFeatureFlags includes all user-controllable flags (MCP Apps +
granular), InsidersFeatureFlags only includes MCPAppsFeatureFlag
- HeaderAllowedFeatureFlags() now delegates to AllowedFeatureFlags
- Builder uses feature checker instead of insidersMode bool
- Remove InsidersOnly field from ServerTool and WithInsidersMode from
Builder
- HTTP feature checker uses ResolveFeatureFlags for per-request
resolution with insiders expansion
- Tool handlers check MCPAppsFeatureFlag via IsFeatureEnabled instead
of InsidersMode
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Sam Morrow
a24c0be254