Auto-categorization, merchant detection/enhancement, and PDF/bank-statement
extraction hard-coded Provider::Registry.get_provider(:openai), so selecting
Anthropic (or running an Anthropic-only self-hosted install) left those
operations using/missing OpenAI rather than the chosen provider.
Add Provider::Registry.preferred_llm_provider, which resolves the LLM provider
honoring Setting.llm_provider with a configured-provider fallback (mirroring how
chat picks its provider), and route all six TODO(#2113) call sites through it:
- Family::AutoCategorizer#llm_provider
- Family::AutoMerchantDetector#llm_provider
- ProviderMerchant::Enhancer#llm_provider
- PdfImport (process_pdf + extract_bank_statement)
- Assistant::Function::ImportBankStatement
Provider::Anthropic already implements auto_categorize / auto_detect_merchants /
enhance_provider_merchants (#1984) and process_pdf / extract_bank_statement
(#1985), so no provider changes are needed — only the wiring.
Closes#2113.
f25fe30a41