Adds the curated Loans A/C steps (security/collateral, amount & tenure, repayment & EMI, interest, prepayment & closure) and a product-type picker (loan-product-types.ts) shared by the create wizard, product list and account picker. The interest step and a new register-rate-view read the live Loan Interest Rate Register for a product's chart/CIBIL rate instead of a hardcoded value, and a new loan-product-catalog service + template card back the loan account stepper's product pick. Also carries forward in-progress Loan Interest Rate Register UI work: an inline Add Slab panel (replacing window.prompt) and a Submit Details dialog for confirming name/effective dates before submitting for approval. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>