Reasoning effort is uncontrollable on OpenAI-compatible providers — no per-provider knob for gateways

[ruttybob]

Problem

Reasoning-effort control exists only for providers whose model ids are listed natively in the matrix:

• coworker/providers/matrix.py — _EFFORT_NATIVE entries (OpenAI Responses lineup) get wire-native effort positions.
• coworker/providers/codex_provider.py honors settings.get("reasoning_effort").
• coworker/providers/openai_provider.py pins reasoning_effort: none reactively when the server rejects tools+effort — but that is a retry path, not user control.

Meanwhile every _compat vendor in the registry (zai, deepseek, kimi, minimax, qwen, xai, …) rides the plain /v1/chat/completions wire with no way for the user to set reasoning effort at all: no per-provider setting, no capability flag, nothing in the settings surfaces. The request goes out with whatever default the server picks — even though many of these backends (GLM, Kimi, Qwen thinking modes) do honor an effort-style parameter.

Proposal

Add a per-provider (or per-model) reasoning-effort knob for _compat providers, routed through the existing thinking-controls envelope so it composes with the 7-level thinking scale rather than introducing a second control:

• Optional field in the provider profile (SecretStore-backed), absent = current behavior (server default).
• Resolve through thinkingLevelMap → wire-native reasoning_effort in the chat-completions kwargs, same shape codex uses.
• Surface it in ProviderSetup / settings for compat vendors.

Notes

• Backward compatible: unset means exactly today's behavior.
• The reactive _pin_reasoning_effort retry keeps working alongside; an explicit user choice should win over the pin where the server allows it.
• If user-defined OpenAI-compatible providers land (Support user-defined OpenAI-compatible providers as first-class entries (not just the hand-curated registry list) #547), this knob should apply to them too — but that is not a dependency: the gap above exists today for the stock registry vendors alone.