## Description
Implements company backfill migration infrastructure for existing
contacts. This is **Part 1 of 2** for the company model production
rollout as described in
[CW-5726](https://linear.app/chatwoot/issue/CW-5726/company-model-setting-it-up-on-production).
Creates jobs and services to associate existing contacts with companies
based on their email domains, filtering out free email providers (gmail,
yahoo, etc.) and disposable addresses.
**What's included:**
- Business email detector service with ValidEmail2 (uses
`disposable_domain?` to avoid DNS lookups)
- Per-account batch job to process contacts for one account
- Orchestrator job to iterate all accounts
- Rake task: `bundle exec rake companies:backfill`
~~*NOTE*: I'm using a hard-coded approach to determine if something is a
"business" email by filtering out emails that are usually personal. I've
also added domains that are common to some of our customers' regions.
This should be simpler. I looked into `Valid_Email2` and I couldn't find
anything to dictate whether an email is a personal email or a business
one. I don't think the approach used in the frontend is valid here.~~
UPDATE: Using `email_provider_info` gem instead.
**Pending - Part 2 (separate PR):** Real-time company creation for new
contacts
## Type of change
- [x] New feature (non-breaking change which adds functionality)
## How Has This Been Tested?
```bash
# Run all new tests
bundle exec rspec spec/enterprise/services/companies/business_email_detector_service_spec.rb \\
spec/enterprise/jobs/migration/company_account_batch_job_spec.rb \\
spec/enterprise/jobs/migration/company_backfill_job_spec.rb
# Run RuboCop
bundle exec rubocop enterprise/app/services/companies/business_email_detector_service.rb \\
enterprise/app/jobs/migration/company_account_batch_job.rb \\
enterprise/app/jobs/migration/company_backfill_job.rb \\
lib/tasks/companies.rake
```
**Performance optimization:**
- Uses `disposable_domain?` instead of `disposable?` to avoid DNS MX
lookups (discovered via tcpdump analysis - `disposable?` was making
network calls for every email, causing 100x slowdown)
## Checklist:
- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [x] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules
---------
Co-authored-by: Sojan Jose <sojan@pepalo.com>