Add new enterprise requirement gate (#23736)

Add new enterprise requirement gate.

Validation:
- `cargo test -p codex-config --lib`
- `cargo test -p codex-app-server-protocol --lib`
- `cargo test -p codex-tui --lib debug_config`
- `cargo test -p codex-app-server --lib` *(fails: stack overflow in
`in_process::tests::in_process_start_initializes_and_handles_typed_v2_request`;
reproduces when run alone)*

codex-rs/app-server-protocol/src/protocol/v2/config.rs

@@ -361,6 +361,7 @@ pub struct ConfigRequirements {
     pub allowed_permissions: Option<Vec<String>>,
     pub allowed_web_search_modes: Option<Vec<WebSearchMode>>,
     pub allow_managed_hooks_only: Option<bool>,
+    pub allow_appshots: Option<bool>,
     pub computer_use: Option<ComputerUseRequirements>,
     pub feature_requirements: Option<BTreeMap<String, bool>>,
     #[experimental("configRequirements/read.hooks")]

codex-rs/app-server-protocol/src/protocol/v2/tests.rs

@@ -1593,6 +1593,7 @@ fn config_requirements_granular_allowed_approval_policy_is_marked_experimental()
             allowed_permissions: None,
             allowed_web_search_modes: None,
             allow_managed_hooks_only: None,
+            allow_appshots: None,
             computer_use: None,
             feature_requirements: None,
             hooks: None,