Fix/313 rename buttons labels

Summary

Renames various buttons and labels across the customs app for consistency, per the UI change proposals doc attached in the issue.

• "Sorry we could not find any transport with that guarantee ID" → "Guarantee ID could not be found."
• Simplified guarantee view: split the territory message by guarantee status - "isn't associated with any TIR Transport..." for Issued, "does not pass through your customs territory..." for any other status
• Operation detail (Termination section): "Remark" → "Reservations"
• Operation detail (Start section): "Remark" → "Miscellaneous (itinerary stipulated, Customs office at which the load must be produced, etc.)"
• eTIR communication error: "...eTIR international system" → "...eTIR International System."
• Guarantee card: "TIR transport guarantee" → "TIR Transport guarantee information"; "International organization" → "International Organization"
• Seals modal title: "Seals and stamps information" → "Customs seals and stamps information"
• Operations table toggle: "Show all operations" → "Show operations in other countries"
• Office selection modal: "Select your active office for this session" → "Customs office of work"

Note: a few other items from the proposal doc (Start Operation wizard step titles, Holders page heading) were already correct in this branch - no change needed there.

closes #313