permissions: derive compatibility policies from profiles (#19392)

## Why

After #19391, `PermissionProfile` and the split filesystem/network
policies could still be stored in parallel. That creates drift risk: a
profile can preserve deny globs, external enforcement, or split
filesystem entries while a cached projection silently loses those
details. This PR makes the profile the runtime source and derives
compatibility views from it.

## What Changed

- Removes stored filesystem/network sandbox projections from
`Permissions` and `SessionConfiguration`; their accessors now derive
from the canonical `PermissionProfile`.
- Derives legacy `SandboxPolicy` snapshots from profiles only where an
older API still needs that field.
- Updates MCP connection and elicitation state to track
`PermissionProfile` instead of `SandboxPolicy` for auto-approval
decisions.
- Adds semantic filesystem-policy comparison so cwd changes can preserve
richer profiles while still recognizing equivalent legacy projections
independent of entry ordering.
- Updates config/session tests to assert profile-derived projections
instead of parallel stored fields.

## Verification

- `cargo test -p codex-core direct_write_roots`
- `cargo test -p codex-core runtime_roots_to_legacy_projection`
- `cargo test -p codex-app-server
requested_permissions_trust_project_uses_permission_profile_intent`



































































---
[//]: # (BEGIN SAPLING FOOTER)
Stack created with [Sapling](https://sapling-scm.com). Best reviewed
with [ReviewStack](https://reviewstack.dev/openai/codex/pull/19392).
* #19395
* #19394
* #19393
* __->__ #19392

codex-rs/core/src/connectors.rs

@@ -17,7 +17,7 @@ use codex_connectors::DirectoryListResponse;
 use codex_exec_server::EnvironmentManager;
 use codex_exec_server::EnvironmentManagerArgs;
 use codex_exec_server::ExecServerRuntimePaths;
-use codex_protocol::protocol::SandboxPolicy;
+use codex_protocol::models::PermissionProfile;
 use codex_tools::DiscoverableTool;
 use rmcp::model::ToolAnnotations;
 use serde::Deserialize;
@@ -274,7 +274,7 @@ pub async fn list_accessible_connectors_from_mcp_tools_with_environment_manager(
         &config.permissions.approval_policy,
         INITIAL_SUBMIT_ID.to_owned(),
         tx_event,
-        SandboxPolicy::new_read_only_policy(),
+        PermissionProfile::default(),
         McpRuntimeEnvironment::new(environment, config.cwd.to_path_buf()),
         config.codex_home.to_path_buf(),
         codex_apps_tools_cache_key(auth.as_ref()),