* Reformat "This is a legacy plan" notice on billing page.
* Add a link to the plan name on upgrade page title.
* Tweak discount style on billing page.
* Add line break to server login page title.
* Match server login page title and tab title.
* For free trial, don't show number of licenses for current billing period.
* For free trial scheduled to downgrade, don't show number of
licenses for next billing period.
Use of `string_id` in the sponsorship request email content was
removed in commit d3834f8b9, but it is still used in the email
subject.
Updates the email subject to use the billing_entity_display_name,
which is still the Realm.string_id for Zulip Cloud organizations.
Sets this string as "billing_entity" in the context and subject
template.
Moves the section in support views for any current plan details
to a new template: `templates/analytics/current_plan_details.html`.
Also, updates the PlanData dataclass to have a boolean that checks
if the current plan tier is the self-hosted legacy plan.
Updates `get_plan_type_string` for RemoteZulipServer plan types and
capitalizes the strings used for Realm plan types.
Also changes the string for Realm.PLAN_TYPE_STANDARD_FREE to be
"Standard free" instead of "open source" as that is used for any
100% sponsored organization, which is not restricted to open-source
projects.
This adds the new tabs from /plans to:
* /for/business
* /self-hosting
And it isolates legacy styles to preserve the tabs on
/for/education
Fixes: #28013
Removes the support actions for changing a remote server's default
discount and sponsorship pending states if the remote server is on
the sponsored plan type.
The "send_invoice" and "charge_automatically" strings used by stripe
for the `collection_method` are referred to both as the "billing
method" and "billing modality" in the billing code.
Because we send this as data to stripe as either `collection_method`
or `billing_modality`, renames any references that are any form of
"billing method".
Analogical to 1df8e00d7c which implemented
this for the RemoteRealm auth flow.
Except here we don't need to add next_page to the IdentityDict
(LegacyServerIdentityDict in this flow), because the redirect happens
immediately at remote_billing_legacy_server_login upon login - so no
need to have a structure to carry the info through intermediate steps.
[squash]: Update sponsorsip and question boxes for Cloud.
[squash]: Update tabs subtitles.
[squash]: Content for info boxes for self-hosted plans.
[squash]: Adjust content to fit design.
portico: Tweak /plans text.
Aman Agrawal
Karl Stolley
Lauryn Menard
Mateusz Mandera
Alya Abbott