Improve baoyu-imagine Replicate compatibility (#125)

* Align Replicate image behavior with the models we actually support

Replicate image generation in baoyu-imagine no longer assumes that every model
accepts the nano-banana request schema. The Replicate provider now defaults to
google/nano-banana-2, routes supported model families through family-specific
builders and validators, blocks misleading multi-output requests before they
reach the API, and updates user-facing docs/config guidance to match the actual
contract.

Constraint: Replicate model families expose different input schemas
Constraint: Current Replicate path only saves one output image per request
Constraint: Must not change non-Replicate providers
Rejected: Keep one nano-banana-style payload for all Replicate models | triggers remote schema errors on Seedream and Wan
Rejected: Continue accepting multi-image Replicate requests and save only the first result | silently drops outputs
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Add a family-specific validator and input builder before exposing more Replicate model IDs or multi-output flags
Tested: npm test
Tested: node --test skills/baoyu-imagine/scripts/providers/replicate.test.ts skills/baoyu-imagine/scripts/main.test.ts
Not-tested: Live Replicate API calls against production models
Co-authored-by: justnode <justnode@users.noreply.github.com>

* Preserve Replicate compatibility when shared defaults leak across providers

Addressed the new PR review findings by teaching baoyu-imagine to track
where aspect-ratio defaults came from, mirroring the earlier imageSize fix,
so unsupported Replicate models can still run prompt-only requests when the
value was inherited from shared config. Also corrected Seedream 4.5 custom
size encoding to use the API's custom width/height schema instead of sending
literal WxH strings.

Constraint: Shared EXTEND defaults still need to apply globally for providers that support them
Constraint: Seedream 4.5 custom sizes must follow Replicate's documented custom size schema
Rejected: Ignore all aspect ratios for unknown Replicate models | would hide explicit unsupported CLI/task input
Rejected: Keep Seedream custom sizes as literal strings | validated locally but fails against the provider API
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Any future inherited-default validation for provider-specific flags should record the source explicitly before rejecting it
Tested: node --import tsx --test skills/baoyu-imagine/scripts/main.test.ts skills/baoyu-imagine/scripts/providers/replicate.test.ts
Tested: npm test
Not-tested: Live Replicate API calls for Seedream 4.5 custom-size requests

---------

Co-authored-by: justnode <justnode@users.noreply.github.com>

README.zh.md

@@ -754,9 +754,15 @@ AI 驱动的生成后端。
 # MiniMax + 角色参考图
 /baoyu-imagine --prompt "A girl stands by the library window, cinematic lighting" --image out.jpg --provider minimax --model image-01 --ref portrait.png --ar 16:9
 
-# Replicate
+# Replicate（默认：google/nano-banana-2）
 /baoyu-imagine --prompt "一只猫" --image cat.png --provider replicate
 
+# Replicate Seedream 4.5
+/baoyu-imagine --prompt "一张影棚人像" --image portrait.png --provider replicate --model bytedance/seedream-4.5 --ar 3:2
+
+# Replicate Wan 2.7 Image Pro
+/baoyu-imagine --prompt "一张概念分镜" --image frame.png --provider replicate --model wan-video/wan-2.7-image-pro --size 2048x1152
+
 # 即梦（Jimeng）
 /baoyu-imagine --prompt "一只可爱的猫" --image cat.png --provider jimeng
 
@@ -784,8 +790,8 @@ AI 驱动的生成后端。
 | `--size` | 尺寸（如 `1024x1024`） |
 | `--quality` | `normal` 或 `2k`（默认：`2k`） |
 | `--imageSize` | Google/OpenRouter 使用的 `1K`、`2K`、`4K` |
-| `--ref` | 参考图片（Google、OpenAI、Azure OpenAI、OpenRouter、Replicate、MiniMax 或 Seedream 5.0/4.5/4.0） |
-| `--n` | 单次请求生成图片数量 |
+| `--ref` | 参考图片（Google、OpenAI、Azure OpenAI、OpenRouter、Replicate 支持的模型家族、MiniMax 或 Seedream 5.0/4.5/4.0） |
+| `--n` | 单次请求生成图片数量（`replicate` 当前只支持 `--n 1`） |
 | `--json` | 输出 JSON 结果 |
 
 **环境变量**（配置方法见[环境配置](#环境配置)）：
@@ -813,7 +819,7 @@ AI 驱动的生成后端。
 | `ZAI_IMAGE_MODEL` | Z.AI 模型 | `glm-image` |
 | `BIGMODEL_IMAGE_MODEL` | Z.AI 模型向后兼容别名 | `glm-image` |
 | `MINIMAX_IMAGE_MODEL` | MiniMax 模型 | `image-01` |
-| `REPLICATE_IMAGE_MODEL` | Replicate 模型 | `google/nano-banana-pro` |
+| `REPLICATE_IMAGE_MODEL` | Replicate 模型 | `google/nano-banana-2` |
 | `JIMENG_IMAGE_MODEL` | 即梦模型 | `jimeng_t2i_v40` |
 | `SEEDREAM_IMAGE_MODEL` | 豆包模型 | `doubao-seedream-5-0-260128` |
 | `OPENAI_BASE_URL` | 自定义 OpenAI 端点 | - |
@@ -844,6 +850,9 @@ AI 驱动的生成后端。
 - MiniMax 参考图会走 `subject_reference`，当前能力更偏角色 / 人像一致性。
 - 即梦不支持参考图。
 - 豆包参考图能力仅适用于 Seedream 5.0 / 4.5 / 4.0，不适用于 Seedream 3.0。
+- Replicate 默认模型改为 `google/nano-banana-2`。`baoyu-imagine` 目前只对 `google/nano-banana*`、`bytedance/seedream-4.5`、`bytedance/seedream-5-lite`、`wan-video/wan-2.7-image` 和 `wan-video/wan-2.7-image-pro` 开启本地能力识别与校验。
+- Replicate 当前只保存单张输出图，`--n > 1` 会在本地直接报错，避免多图结果被静默丢弃。
+- Replicate 的参数能力按模型家族区分：nano-banana 走 `--quality` / `--ar`，Seedream 走校验后的 `--size` / `--ar`，Wan 走校验后的 `--size`（`--ar` 会先在本地换算成具体尺寸）。
 
 **服务商自动选择**：
 1. 如果指定了 `--provider` → 使用指定的
@@ -1161,7 +1170,7 @@ MINIMAX_IMAGE_MODEL=image-01
 
 # Replicate
 REPLICATE_API_TOKEN=r8_xxx
-REPLICATE_IMAGE_MODEL=google/nano-banana-pro
+REPLICATE_IMAGE_MODEL=google/nano-banana-2
 # REPLICATE_BASE_URL=https://api.replicate.com
 
 # 即梦（Jimeng）