app-server-protocol: mark permission profiles experimental (#19899)

## Why

`PermissionProfile` is now the canonical internal permissions
representation, but the app-server wire shape is still intentionally
unstable while the migration continues. Stable app-server clients should
not see or generate code for these fields until the wire format settles.

## What changed

- Marks every app-server v2 field that sends `PermissionProfile` as
experimental, including `command/exec`, `thread/start`, `thread/resume`,
`thread/fork`, and `turn/start` request/response payloads.
- Enables per-field experimental inspection for `command/exec`, so
`permissionProfile` is gated without making the entire method
experimental.
- Fixes the generated TypeScript schema filter to be comment-aware. The
previous scanner treated apostrophes inside doc comments as string
delimiters, so some experimental fields leaked into stable TypeScript
even though stable JSON was filtered correctly.

## Verification

- `cargo test -p codex-app-server-protocol`










---
[//]: # (BEGIN SAPLING FOOTER)
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with [ReviewStack](https://reviewstack.dev/openai/codex/pull/19899).
* #19900
* __->__ #19899

codex-rs/app-server-protocol/schema/json/ClientRequest.json

@@ -218,17 +218,6 @@
             "null"
           ]
         },
-        "permissionProfile": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/PermissionProfile"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "description": "Optional full permissions profile for this command.\n\nDefaults to the user's configured permissions when omitted. Cannot be combined with `sandboxPolicy`."
-        },
         "processId": {
           "description": "Optional client-supplied, connection-scoped process id.\n\nRequired for `tty`, `streamStdin`, `streamStdoutStderr`, and follow-up `command/exec/write`, `command/exec/resize`, and `command/exec/terminate` calls. When omitted, buffered execution gets an internal id that is not exposed to the client.",
           "type": [
@@ -3271,17 +3260,6 @@
             "null"
           ]
         },
-        "permissionProfile": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/PermissionProfile"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "description": "Full permissions override for the forked thread. Cannot be combined with `sandbox`."
-        },
         "sandbox": {
           "anyOf": [
             {
@@ -3687,17 +3665,6 @@
             "null"
           ]
         },
-        "permissionProfile": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/PermissionProfile"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "description": "Full permissions override for the resumed thread. Cannot be combined with `sandbox`."
-        },
         "personality": {
           "anyOf": [
             {
@@ -3881,17 +3848,6 @@
             "null"
           ]
         },
-        "permissionProfile": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/PermissionProfile"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "description": "Full permissions override for this thread. Cannot be combined with `sandbox`."
-        },
         "personality": {
           "anyOf": [
             {
@@ -4103,17 +4059,6 @@
         "outputSchema": {
           "description": "Optional JSON Schema used to constrain the final assistant message for this turn."
         },
-        "permissionProfile": {
-          "anyOf": [
-            {
-              "$ref": "#/definitions/PermissionProfile"
-            },
-            {
-              "type": "null"
-            }
-          ],
-          "description": "Override the full permissions profile for this turn and subsequent turns. Cannot be combined with `sandboxPolicy`."
-        },
         "personality": {
           "anyOf": [
             {