feat(codex): OpenAI Codex as an iii worker

.github/workflows/create-tag.yml

@@ -12,6 +12,7 @@ on:
           - acp
           - claude-code
           - coder
+          - codex
           - console
           - context-manager
           - database

.github/workflows/release.yml

@@ -7,6 +7,7 @@ on:
       - 'acp/v*'
       - 'claude-code/v*'
       - 'coder/v*'
+      - 'codex/v*'
       - 'console/v*'
       - 'context-manager/v*'
       - 'database/v*'

README.md

@@ -40,6 +40,7 @@ npx skills add iii-hq/iii --all
 |---|---|---|
 | [`acp`](acp/) | Rust | Agent Client Protocol surface — stdio JSON-RPC, exposes iii agents as ACP sessions. |
 | [`harness`](harness/) | Node | TS port of the iii harness stack — bundles `harness` (provider registry + credentials/settings/permissions via the `configuration` worker), `turn-orchestrator`, `approval-gate`, `hook-fanout`, `models-catalog`, the `provider-*` workers, `llm-budget`, and `context-compaction` as one pnpm monorepo. Conversations persist in `session-manager`. See [`harness/README.md`](harness/README.md). |
+| [`codex`](codex/) | Rust | OpenAI Codex as an iii worker — `codex::*` spawn the codex CLI for headless turns, mirror raw thread events onto `codex::events`, and stream AgentEvent frames onto `agent::events`. |
 | [`claude-code`](claude-code/) | Node | Claude Code as an iii worker — `claude::*` runs headless Claude Code turns, mirrors raw messages onto `claude::events`, and streams AgentEvent frames onto `agent::events`. |
 | [`session-manager`](session-manager/) | Rust | Durable, reactive, branching conversation store — fourteen `session::*` functions plus six trigger types; the transcript backend for `harness` and `console`. See [`session-manager/architecture/`](session-manager/architecture/). |
 | [`context-manager`](context-manager/) | Rust | Model-ready context assembly — four `context::*` functions for token counting, function-result pruning, and history compaction over caller-supplied messages. Storage-agnostic; summarisation via `llm-router` when installed. |

codex/.gitignore

@@ -0,0 +1,2 @@
+/target
+*.tsbuildinfo