Phase 2: Rust Workspace Transformation (Part 1)

- Renamed directory: codex-backend-openapi-models -> llmx-backend-openapi-models
- Updated all Cargo.toml files:
  - Package names: codex-* -> llmx-*
  - Library names: codex_* -> llmx_*
  - Workspace dependencies updated
- Renamed Rust source files:
  - codex*.rs -> llmx*.rs (all modules)
  - codex_conversation -> llmx_conversation
  - codex_delegate -> llmx_delegate
  - codex_message_processor -> llmx_message_processor
  - codex_tool_* -> llmx_tool_*
- Updated all Rust imports:
  - use codex_* -> use llmx_*
  - mod codex* -> mod llmx*
- Updated environment variables in code:
  - CODEX_HOME -> LLMX_HOME
  - .codex -> .llmx paths
- Updated protocol crate lib name for proper linking

Note: Some compilation errors remain (type inference issues) but all
renaming is complete. Will fix compilation in next phase.

🤖 Generated with Claude Code

llmx-rs/responses-api-proxy/src/main.rs

@@ -1,12 +1,12 @@
 use clap::Parser;
-use codex_responses_api_proxy::Args as ResponsesApiProxyArgs;
+use llmx_responses_api_proxy::Args as ResponsesApiProxyArgs;
 
 #[ctor::ctor]
 fn pre_main() {
-    codex_process_hardening::pre_main_hardening();
+    llmx_process_hardening::pre_main_hardening();
 }
 
 pub fn main() -> anyhow::Result<()> {
     let args = ResponsesApiProxyArgs::parse();
-    codex_responses_api_proxy::run_main(args)
+    llmx_responses_api_proxy::run_main(args)
 }