feat(filters): refactor folder-rule-collector to folder-memory

- Rename plugin from `folder-rule-collector` to `folder-memory` for better clarity.
- Refactor code to focus on "Project Rules" collection, removing "Knowledge" collection for V1.
- Add `PRIORITY` valve (default: 20) to ensure execution after context compression.
- Update all parameter names to uppercase for consistency.
- Update documentation (README, global docs) with GitHub raw URL for demo image.
- Remove `STATUS` valve as it's redundant with OpenWebUI's built-in function toggle.
- Add `ROADMAP.md` to track future "Project Knowledge" features.
- Update `.github/copilot-instructions.md` with detailed commit message guidelines.

README_CN.md

@@ -50,6 +50,7 @@ OpenWebUI 增强功能集合。包含个人开发与收集的插件、提示词
 #### Filters (消息处理)
 - **Async Context Compression** (`async-context-compression`): 异步上下文压缩，优化 Token 使用。
 - **Context Enhancement** (`context_enhancement_filter`): 上下文增强过滤器。
+- **Folder Memory** (`folder-memory`): 自动从对话中提取项目规则并注入到文件夹系统提示词中。
 - **Gemini Manifold Companion** (`gemini_manifold_companion`): Gemini Manifold 配套增强。
 - **Gemini Multimodal Filter** (`web_gemini_multimodel_filter`): 为任意模型提供多模态能力（PDF、Office、视频等），支持智能路由和字幕精修。
 - **Markdown Normalizer** (`markdown_normalizer`): 修复 LLM 输出中常见的 Markdown 格式问题。