Adds a shared Export to Excel utility (investment-export.ts) and wires it into every listing/report screen in the Investment module — Dashboard (break-up + allocation), Reports (all ~20 report shapes), Interest (per active tab), the FD/Bond/Share Holdings registers, and Masters (per active master tab). Entry/transaction forms intentionally have no export button. No sign-off is included here, matching the request to keep that feature reconciliation-only. Also fixes the Reconciliation export flow: the Prepared/Checked/Approved sign-off is now an optional one-off popup shown when "Export to Excel" is clicked (fields are blank by default and downloading works whether or not they're filled), replacing the earlier always-visible sign-off card. Also fixes three reconciliation reports (Sundry Dr/Cr, NEFT/RTGS, UDIR) whose labels contain "/" — an Excel-forbidden worksheet-name character — which was silently aborting their export.