feat(share): add chat

[ycdzj]

• refactor(shares): add validate-share decorator
• refactor(resources): add getAllSubResources
• refactor(stream): add computeVisibleResources
• refactor(messages): nullable user_id
• refactor(wizard): update agent stream
• refactor(messages): specify type for userId
• refactor(stream): update getUserVisibleResources
• refactor(resources): update shared-resource-meta
• refactor(shares): add create conversations api

[Copilot]

Pull Request Overview

This PR implements chat functionality for shared resources by adding comprehensive support for conversations within shares. The implementation includes API endpoints for creating and accessing conversations through shares, proper validation mechanisms, and necessary database schema changes.

• Added new controllers and services to handle shared wizard and conversation functionality
• Implemented share validation decorators and interceptors for secure access control
• Updated existing services to support nullable user IDs for anonymous share conversations

Reviewed Changes

Copilot reviewed 37 out of 37 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/wizard/wizard.service.ts	Updated to accept namespaceId as parameter and added dependencies for shared resources
src/wizard/wizard.controller.ts	Refactored into multiple controllers with namespace-aware routing and added SharedWizardController
src/wizard/stream.service.ts	Enhanced with share-specific resource visibility and agent stream creation methods
src/shared-resources/shared-resources.service.ts	Simplified API to use Share objects directly and added getAllSharedResources method
src/conversations/conversations.service.ts	Added support for share-based conversations with nullable user IDs
src/interceptor/validate-share.interceptor.ts	New interceptor for automatic share validation and chat permission checking
src/decorators/validate-share.decorator.ts	New decorators for share validation and injection
src/messages/entities/message.entity.ts	Made userId nullable to support anonymous share conversations
src/migrations/	Database migrations for nullable user IDs and share-conversation relationships

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