[codex] Consolidate shared prompts in codex-prompts (#25151)

## Why

`codex_core` is consistently a bottleneck for incremental builds during
iteration. The simplest fix is to make the crate smaller.

## Summary

`codex-core` owns several reusable prompt renderers and static prompt
assets, which makes the crate harder to split apart.

Rename `codex-review-prompts` to `codex-prompts` and move shared review,
goal, permissions, compaction, realtime, hierarchical AGENTS.md, and
`apply_patch` prompts into it. Move prompt-only tests and update
consumers and `CODEOWNERS`.

## Validation

- `just test -p codex-prompts -p codex-apply-patch`
- `just test -p codex-core prompt_caching`
- Bazel builds for the affected crates

codex-rs/prompts/src/lib.rs

@@ -0,0 +1,27 @@
+mod agents;
+mod apply_patch;
+mod compact;
+mod goals;
+mod permissions_instructions;
+mod realtime;
+mod review_exit;
+mod review_request;
+
+pub use agents::HIERARCHICAL_AGENTS_MESSAGE;
+pub use apply_patch::APPLY_PATCH_TOOL_INSTRUCTIONS;
+pub use compact::SUMMARIZATION_PROMPT;
+pub use compact::SUMMARY_PREFIX;
+pub use goals::budget_limit_prompt;
+pub use goals::continuation_prompt;
+pub use goals::objective_updated_prompt;
+pub use permissions_instructions::PermissionsInstructions;
+pub use realtime::BACKEND_PROMPT;
+pub use realtime::END_INSTRUCTIONS;
+pub use realtime::START_INSTRUCTIONS;
+pub use review_exit::render_review_exit_interrupted;
+pub use review_exit::render_review_exit_success;
+pub use review_request::REVIEW_PROMPT;
+pub use review_request::ResolvedReviewRequest;
+pub use review_request::resolve_review_request;
+pub use review_request::review_prompt;
+pub use review_request::user_facing_hint;