chore(gitignore): ignore user-local ev-profiles JSON files (#1982)

chore(gitignore): ignore user-local ev-profiles JSON files (#1982)

Add `src/assets/ev-profiles*.json` with negation for
`ev-profiles-template.json`, alongside the existing `config` and
`idtags` patterns. The three pairs are semantically identical:
user-mutable local instance + committed template.

The `ev-profiles.json` user file was previously untracked and
surfaced as noise in `git status`; the template
(`ev-profiles-template.json`) is documented in the README as the
canonical starting point for the `evProfilesFile` template field
consumed by the coherent MeterValues generator.

Verified with `git check-ignore -v`:
- `src/assets/ev-profiles.json`         → matched by .gitignore:7
- `src/assets/ev-profiles-template.json` → NOT ignored (negation)