Add Keybase integration (#10297)

* create account_identity_proofs table

* add endpoint for keybase to check local proofs

* add async task to update validity and liveness of proofs from keybase

* first pass keybase proof CRUD

* second pass keybase proof creation

* clean up proof list and add badges

* add avatar url to keybase api

* Always highlight the “Identity Proofs” navigation item when interacting with proofs.

* Update translations.

* Add profile URL.

* Reorder proofs.

* Add proofs to bio.

* Update settings/identity_proofs front-end.

* Use `link_to`.

* Only encode query params if they exist.

URLs without params had a trailing `?`.

* Only show live proofs.

* change valid to active in proof list and update liveness before displaying

* minor fixes

* add keybase config at well-known path

* extremely naive feature flagging off the identity proof UI

* fixes for rubocop

* make identity proofs page resilient to potential keybase issues

* normalize i18n

* tweaks for brakeman

* remove two unused translations

* cleanup and add more localizations

* make keybase_contacts an admin setting

* fix ExternalProofService my_domain

* use Addressable::URI in identity proofs

* use active model serializer for keybase proof config

* more cleanup of keybase proof config

* rename proof is_valid and is_live to proof_valid and proof_live

* cleanup

* assorted tweaks for more robust communication with keybase

* Clean up

* Small fixes

* Display verified identity identically to verified links

* Clean up unused CSS

* Add caching for Keybase avatar URLs

* Remove keybase_contacts setting

config/locales/en.yml

@@ -633,6 +633,21 @@ en:
     validation_errors:
       one: Something isn't quite right yet! Please review the error below
       other: Something isn't quite right yet! Please review %{count} errors below
+  identity_proofs:
+    active: Active
+    authorize: Yes, authorize
+    authorize_connection_prompt: Authorize this cryptographic connection?
+    errors:
+      failed: The cryptographic connection failed. Please try again from %{provider}.
+      keybase:
+        invalid_token: Keybase tokens are hashes of signatures and must be 66 hex characters
+        verification_failed: Keybase does not recognize this token as a signature of Keybase user %{kb_username}. Please retry from Keybase.
+    explanation_html: Here you can cryptographically connect your other identities, such as a Keybase profile. This lets other people send you encrypted messages and trust content you send them.
+    i_am_html: I am %{username} on %{service}.
+    identity: Identity
+    inactive: Inactive
+    status: Verification status
+    view_proof: View proof
   imports:
     modes:
       merge: Merge
@@ -835,6 +850,7 @@ en:
     edit_profile: Edit profile
     export: Data export
     featured_tags: Featured hashtags
+    identity_proofs: Identity proofs
     import: Import
     migrate: Account migration
     notifications: Notifications