Fire Behaviour Calculator (old): add new row position / interaction

**As a** *FBAN* **I want** *new rows I create to be visible and easily accessible in the table* **So That** *adding and populating new rows is clear, easy and fast*

**Additional Context**
- current behaviour: if I add a new row to long list ~9-10+ Wx, the row is added to the bottom of the table. If I haven't scrolled down the table, I can't see the new row. No feedback that it was added, have to go looking for it to populate. If I scroll down to the bottom of the table and then add a new row, same thing, I still can't see the new row added. **In usability testing, users click add row multiple times and insist its broken: "nothing happens".**
- **For investigation:** I'm curious if we can auto-scroll the table to the new row when it is added. We can also add the new row to the top of the table by default (auto-scroll would still be useful if someone doesn't have the top of table in view)
- Scenario 1: I load a bookmark, it is long, I want to add a new station, I didn't scroll yet, I add station, it is at the top.
- Scenario 2: I load a bookmark, I scrolled through the table, saw a station was missing, add new station, it is added to the top, the table scrolls to ensure that row is visible.
- Scenario 3: I'm building a new list, and add new rows one by one until I get to 20, populating them as I go. As I add new rows, the table scrolls down to ensure the new rows are visible.
- Scenario 4: I'm building a new list, add the number of empty rows I need, then populate them one by one (less relevant to this ticket)

**Acceptance Criteria**
- [ ] Given (Context), When (action carried out), Then (expected outcome)
- [ ] Given (Context), When (action carried out), Then (expected outcome)

**Definition of Done**
- [ ] Ready to Demo in Sprint Review
- [ ] Does what I have made have appropriate test coverage?
- [ ] Documentation and/or scientific documentation exists and can be found
- [ ] Peer Reviewed by 2 people on the team
- [ ] Manual testing of all PRs in Dev and Prod
- [ ] Merged

No file, test, or entry point is named. Reproduce the add-row behavior in the old Fire Behaviour Calculator with both short and long tables, then trace the table and add-row implementation. Done means newly added rows are visibly accessible in each described scenario and the behavior has appropriate test coverage.

Written by the indexing model from the issue text.