permissions: remove macOS seatbelt extension profiles (#15918)

## Why

`PermissionProfile` should only describe the per-command permissions we
still want to grant dynamically. Keeping
`MacOsSeatbeltProfileExtensions` in that surface forced extra macOS-only
approval, protocol, schema, and TUI branches for a capability we no
longer want to expose.

## What changed

- Removed the macOS-specific permission-profile types from
`codex-protocol`, the app-server v2 API, and the generated
schema/TypeScript artifacts.
- Deleted the core and sandboxing plumbing that threaded
`MacOsSeatbeltProfileExtensions` through execution requests and seatbelt
construction.
- Simplified macOS seatbelt generation so it always includes the fixed
read-only preferences allowlist instead of carrying a configurable
profile extension.
- Removed the macOS additional-permissions UI/docs/test coverage and
deleted the obsolete macOS permission modules.
- Tightened `request_permissions` intersection handling so explicitly
empty requested read lists are preserved only when that field was
actually granted, avoiding zero-grant responses being stored as active
permissions.

codex-rs/core/README.md

@@ -17,32 +17,8 @@ pointer file), the resolved `gitdir:` target, and `.codex` read-only.
 Network access and filesystem read/write roots are controlled by
 `SandboxPolicy`. Seatbelt consumes the resolved policy and enforces it.
 
-Seatbelt also supports macOS permission-profile extensions layered on top of
-`SandboxPolicy`:
-
-- no extension profile provided:
-  keeps legacy default preferences read access (`user-preference-read`).
-- extension profile provided with no `macos_preferences` grant:
-  does not add preferences access clauses.
-- `macos_preferences = "readonly"`:
-  enables cfprefs read clauses and `user-preference-read`.
-- `macos_preferences = "readwrite"`:
-  includes readonly clauses plus `user-preference-write` and cfprefs shm write
-  clauses.
-- `macos_automation = true`:
-  enables broad Apple Events send permissions.
-- `macos_automation = ["com.apple.Notes", ...]`:
-  enables Apple Events send only to listed bundle IDs.
-- `macos_launch_services = true`:
-  enables LaunchServices lookups and open/launch operations.
-- `macos_accessibility = true`:
-  enables `com.apple.axserver` mach lookup.
-- `macos_calendar = true`:
-  enables `com.apple.CalendarAgent` mach lookup.
-- `macos_contacts = "read_only"`:
-  enables Address Book read access and Contacts read services.
-- `macos_contacts = "read_write"`:
-  includes the readonly Contacts clauses plus Address Book writes and keychain/temp helpers required for writes.
+Seatbelt also keeps the legacy default preferences read access
+(`user-preference-read`) needed for cfprefs-backed macOS behavior.
 
 ### Linux