[video recordings] Send email notifications to speakers when video recordings are first published.

[jayaddison]

Resolves #1259.

Note: untested because I don't currently have a functional local dev env (any help testing this is appreciated!)

[jayaddison]

Based on local testing, this seems to be working; email notifications are sent the first time that c3voc_url or youtube_url are set on the proposal, and this updates the database accordingly. Lost videos cannot be updated after the flag is set.

app_1         | Subject: Your EMF youth workshop video recording has been published ('Commodi
app_1         |  praesentium dignissimos et sed.')
app_1         | From: Electromagnetic Field <speakers@emfcamp.org>
app_1         | To: fryolivia@example.org
app_1         | Date: Thu, 08 Aug 2024 10:53:53 -0000
app_1         | Message-ID: <172311443340.165.9383873297324877052@3dd7f43481ce>
app_1         | 
app_1         | 
app_1         | ============================================================================
app_1         | This message was not sent from production.
app_1         | 
app_1         | If you did not expect an email, please get in touch at contact@emfcamp.org.
app_1         | ============================================================================
app_1         | 
app_1         | Hi Mrs Amanda Jackson,
app_1         | 
app_1         | The video recording for your EMF youth workshop 'Commodi praesentium dignissimos et sed.' has been edited and published!
app_1         | 
app_1         | The video and direct links to it can be found at: https://www.emfcamp.org/schedule/2024/8
app_1         | 
app_1         | Thank you again for participating in EMF 2024!
app_1         | 
app_1         | -------------------------------------------------------------------------------
app_1         | 2024-08-08 10:53:53,415 werkzeug     INFO     165 p4glzggh     127.0.0.1 - - [08/Aug/2024 10:53:53] "PATCH /api/proposal/8 HTTP/1.1" 200 -
app_1         | 2024-08-08 10:53:55,324 werkzeug     INFO     165 None         127.0.0.1 - - [08/Aug/2024 10:53:55] "PATCH /api/proposal/8 HTTP/1.1" 200 -

[jayaddison]

From testing at ef6f3e0, the messaging is slightly improved (note the more-readable URL).

[app]        | Subject: Your EMF youth workshop video recording has been published ('Dicta
[app]        |  nobis
[app]        |  dignissimos.')
[app]        | From: Electromagnetic Field <speakers@emfcamp.org>
[app]        | To: colinfrost@example.org
[app]        | Date: Mon, 19 Aug 2024 18:57:18 -0000
[app]        | Message-ID: <172409383871.205.12728254549261282028@ba35d978d984>
[app]        | 
[app]        | 
[app]        | ============================================================================
[app]        | This message was not sent from production.
[app]        | 
[app]        | If you did not expect an email, please get in touch at contact@emfcamp.org.
[app]        | ============================================================================
[app]        | 
[app]        | Hi Katherine O'Brien,
[app]        | 
[app]        | The video recording for your EMF youth workshop 'Dicta nobis dignissimos.' has been edited and published!
[app]        | 
[app]        | The video and direct links to it can be found at: http://127.0.0.1:2342/schedule/2024/42-dicta-nobis-dignissimos
[app]        | 
[app]        | Thank you again for participating in EMF 2024!
[app]        | 
[app]        | -------------------------------------------------------------------------------
[app]        | 2024-08-19 18:57:18,722 werkzeug     INFO     205 trptfry4     10.89.1.28 - - [19/Aug/2024 18:57:18] "PATCH /api/proposal/42 HTTP/1.1" 200 -

[jayaddison]

From testing at ef6f3e0, the messaging is slightly improved (note the more-readable URL).

(well, the path part of it, anyway)

[russss]

I've added some additional comments to the issue.