refactor(builder): move ai feature data access into business services

[realcodesiman]

Summary

• Removes every direct db.* call from the builder AI surface (Claude/DeepSeek/Gemini/OpenAI connect actions and queries, ai-files, ai-functions, ai-mcp-servers, ai-triggers, personas) per .agents/rules/data-access.md, so the logic is reusable from the worker and public APIs and mockable at one boundary.
• One of seven parallel scope PRs following feat(contacts): cover full public API for MCP, move logic into business services #1093 (contacts); all are based on main and only append to the shared barrels.

Changes

• packages/business/src/integration-{claude,deepseek,gemini,openai}/service.ts: new connect() mirroring integrationOpenRouterService.connect (audit stays unconditional as before; OpenAI records audit with an explicit workspaceId because authActionClient has no workspace in the audit context).
• New packages/business/src/ai-file/ (create, delete, listWithEmbeddingStatus) and packages/business/src/ai-trigger/ (list, create, duplicate); aiFunctionService.list; integrationMessengerRepository.listPersonasByWorkspaceId.
• Builder actions/queries are thin wrappers; AI cache invalidation stays in the builder because business must not import @chatbotx.io/ai.
• Tests moved to the service boundary (packages/business/__tests__/{integration-llm-connect,ai-file,ai-trigger}.service.test.ts, apps/builder/__tests__/{integration-llm-connect-actions,ai-triggers-actions}.test.ts).

Notes for reviewers

• The four connect() update paths now run the UPDATE outside a transaction (the insert path is still transactional); the old action wrapped the read+update in one transaction. Idempotent by existing.id, so no data-loss window, but flagging the shape change.
• Pre-existing bug preserved verbatim (not fixed here): aiFileService.delete deletes embeddings by aiEmbeddingModel.id instead of aiFileId (harmless via FK cascade).
• Follow-ups listed in the plan: integration-*/actions/update.action.ts and ai-triggers/actions/{update,delete}.action.ts still use db; connectOpenAIAction uses authActionClient and does not verify workspace membership.

Test plan

• pnpm --filter @chatbotx.io/database check-types && test
• pnpm --filter @chatbotx.io/business check-types && test (only the pre-existing ads-conversion-rule.service.test.ts failures remain, also red on main)
• pnpm --filter builder check-types && test
• pnpm lint
• Manual: connect + reconnect each provider in Settings → Integrations; upload/delete a Knowledge file; create/duplicate an AI trigger; Set Persona picker lists personas