Japanese (ja) Translation: Complete translation of contrib and tech_tips sections

## Summary

We have completed a Japanese (ja) translation of FTC Docs and would like to discuss the path forward for making this available to Japanese-speaking *FIRST* Tech Challenge teams.

## What has been done

A full Japanese translation of FTC Docs has been created across 8 pull-request slices covering all major sections:

| PR | Sections |
|----|---------|
| PR 1 | Core pages |
| PR 2 | `hardware_and_software_configuration` |
| PR 3 | `control_hard_compon`, `ftc_sdk`, `devices` |
| PR 4 | `apriltag`, `color_processing`, `cad_resources` |
| PR 5 | `manufacturing` |
| PR 6 | `programming_resources` (part 1) |
| PR 7 | `programming_resources` (part 2) |
| PR 8 | `contrib`, `tech_tips` (**just completed**) |

All `.po` files are fully translated (msgstr entries filled) with consistent terminology in Japanese.

Translation work is maintained at: https://github.com/neipia271828/ftcdocs

## Questions for the FTC Docs team

1. **Official pipeline**: The workflow diagram shows translation going through a dedicated Translation Repo and Transifex. Would it be possible to add Japanese (`ja`) as an officially supported language alongside the existing Spanish (`es`) and French (`fr`) pipelines?

2. **License / ToS clarification**: The Terms of Service state that content may not be translated without express prior written permission. However, since translation `.po` file scaffolding is already present in the repository and Transifex integration exists, we would appreciate clarification on whether contributing translations via PR is considered an authorized form of contribution.

3. **Preferred submission format**: Should we submit translations directly to the `FTC Docs Translation Repo` referenced in the workflow, or via PR to the main `ftcdocs` repository? We want to follow the process that works best for the team.

## Context

Japanese is spoken by a growing number of *FIRST* Tech Challenge teams in Japan and Japanese-speaking communities worldwide. Having official Japanese documentation would significantly lower the barrier to entry for these teams.

We are happy to maintain the Japanese translations on an ongoing basis and address any review feedback from the team.

Thank you for considering this request!