Email threading, cleanup and inbox

[coderberry]

Type of PR

• [x] feature
• [ ] enhancement
• [ ] bug fix
• [ ] other

Description

Checklist

• [x] My code follows the style guidelines of this project & the tests are passing
• [x] I have performed a self-review of my own code
• [x] I have requested a review from another developer(s)

Screenshots

[codecov[bot]]

Codecov Report

Merging #1304 into master will increase coverage by 0.14%. The diff coverage is 49.31%.

@@            Coverage Diff             @@
##           master    #1304      +/-   ##
==========================================
+ Coverage   34.51%   34.66%   +0.14%     
==========================================
  Files         344      346       +2     
  Lines        7952     8010      +58     
==========================================
+ Hits         2745     2777      +32     
- Misses       5207     5233      +26     

Impacted Files	Coverage Δ
app/controllers/emails_controller.rb	0.00% <0.00%> (ø)
app/models/email_user.rb	100.00% <ø> (ø)
app/models/user.rb	79.56% <ø> (ø)
app/reflexes/emails_reflex.rb	0.00% <0.00%> (ø)
app/models/concerns/emails/presentable.rb	71.42% <71.42%> (ø)
app/models/email.rb	85.00% <76.92%> (-8.34%)	:arrow_down:
app/components/page_component.rb	100.00% <100.00%> (ø)
app/mailboxes/incoming_mailbox.rb	65.85% <100.00%> (+0.85%)	:arrow_up:
app/models/concerns/users/presentable.rb	94.44% <100.00%> (ø)
app/jobs/schedule_organization_report_job.rb	86.20% <0.00%> (ø)
... and 2 more