feat(router): harden routing, Claude print turns, and native image passthrough

[gui-drumond]

Summary

Hardens the LoomRouter proxy around the failure modes found in real routed sessions: Claude Code print turns were being denied tool access, Codex native image generation was falling through to a 404, and the Codex config patch was not preserving foreign settings written by the desktop app.

Why

• Claude Code runs through claude -p, which has no interactive approval channel. Without an explicit permission mode and trusted project entry, the model reports that it cannot write files or run commands.
• The proxy only registered Responses, models, and chat routes. Codex image generation and edit calls therefore hit the fallback and returned 404 before reaching the native backend.
• Codex Desktop can rewrite ~/.codex/config.toml and reorder or drop managed markers. The existing patch needed stronger ownership and rollback handling.

Changes

• Claude Code print turns now pass an explicit permission mode, defaulting to acceptEdits, with LOOM_CLAUDE_PERMISSION_MODE as an override.
• ~/.claude.json gets the selected workspace marked as trusted before non-interactive turns.
• Claude child processes recover the login shell PATH, so bun, cargo, and other project tools are visible when the app was launched from Finder.
• Codex status now reports config parseability and local auth session presence/expiry without exposing the token.
• Codex config patching hoists foreign tables out of the managed block and persists previous root values for safer rollback.
• Tool translation now normalizes union-root schemas and whole-number JSON arguments that strict providers otherwise reject.
• Native Codex image generation/edit routes are forwarded to the ChatGPT image backend.
• Added regression coverage for Claude Code subagent args through the LoomRouter subagent path.

Validation

• cargo fmt --manifest-path src-tauri/Cargo.toml --check
• cargo clippy --manifest-path src-tauri/Cargo.toml --all-targets -- -D warnings
• cargo test --manifest-path src-tauri/Cargo.toml
• bun run lint
• bun run test
• bun run build

Non-goals

• Does not adopt a new UI or session log surface.
• Does not add raw image generation through third-party providers.
• Does not replace the existing routing architecture.