Expand Codex protocol and plugin compatibility

[hereww]

What changed

• add Responses API to Chat Completions protocol conversion, including streaming, tools, reasoning, usage, and error mapping
• embed and register the official remote plugin marketplace cache, and update renderer marketplace compatibility
• make Codex SQLite discovery and session backup/restore work across supported database layouts
• synchronize user-script runtime state and refine relay routing, settings, diagnostics, and related UI behavior
• add parity, protocol, marketplace, SQLite, runtime, and routing coverage

Why

Recent Codex app and provider variants use different protocol, marketplace, and local-state layouts. These changes keep CodexTools compatible across those variants while preserving tool calls, reasoning output, plugin discovery, session actions, and script state.

Impact

Users can route Responses API requests through Chat Completions-compatible providers, use the bundled official remote plugin marketplace, and manage sessions and scripts consistently across current Codex layouts.

Validation

• go test ./...
• npm --prefix web run check
• npm --prefix web run vite:build
• git diff --cached --check
• embedded ZIP integrity check with unzip -t