[PM-10648] Remove block legacy users feature flag

[quexten]

🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-10648

📔 Objective

Blocks legacy users on all clients except web for self-hosted customers too. We need to migrate them so we can remove dangerous legacy code.

📸 Screenshots

⏰ Reminders before review

• Contributor guidelines followed
• All formatters and local linters executed and passed
• Written new unit and / or integration tests where applicable
• Protected functional changes with optionality (feature flags)
• Used internationalization (i18n) for all UI strings
• CI builds passed
• Communicated to DevOps any deployment requirements
• Updated any necessary documentation (Confluence, contributing docs) or informed the documentation team

🦮 Reviewer guidelines

• 👍 (:+1:) or similar for great changes
• 📝 (:memo:) or ℹ️ (:information_source:) for notes or general info
• ❓ (:question:) for questions
• 🤔 (:thinking:) or 💭 (:thought_balloon:) for more open inquiry that's not quite a confirmed issue and could potentially benefit from discussion
• 🎨 (:art:) for suggestions / improvements
• ❌ (:x:) or ⚠️ (:warning:) for more significant problems or concerns needing attention
• 🌱 (:seedling:) or ♻️ (:recycle:) for future improvements or indications of technical debt
• ⛏ (:pick:) for minor or nitpick changes

[github-actions]

LaunchDarkly flag references

❌ 1 flag removed

Name	Key	Aliases found	Info
Block Legacy Users	block-legacy-users		✅ all references removed

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 43.70%. Comparing base (cd7c4bf) to head (23a71df).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #5212   +/-   ##
=======================================
  Coverage   43.70%   43.70%           
=======================================
  Files        1469     1469           
  Lines       67901    67898    -3     
  Branches     6156     6155    -1     
=======================================
- Hits        29673    29672    -1     
  Misses      36934    36934           
+ Partials     1294     1292    -2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[github-actions]

Checkmarx One – Scan Summary & Details – 6b80c20b-d9d1-44a7-b785-e3ab390d2b59

New Issues

Severity	Issue	Source File / Package	Checkmarx Insight
	Privacy_Violation	/src/Core/NotificationHub/NotificationHubPushNotificationService.cs: 195	Attack Vector
	Privacy_Violation	/src/Api/Vault/Models/Request/CipherRequestModel.cs: 173	Attack Vector
	Privacy_Violation	/src/Core/Auth/Services/Implementations/AuthRequestService.cs: 214	Attack Vector
	Privacy_Violation	/src/Api/Vault/Models/Request/CipherRequestModel.cs: 202	Attack Vector
	Log_Forging	/src/Api/Auth/Controllers/AccountsController.cs: 972	Attack Vector
	Log_Forging	/src/Api/Tools/Controllers/SendsController.cs: 193	Attack Vector
	Log_Forging	/src/Api/Tools/Controllers/SendsController.cs: 157	Attack Vector
	Log_Forging	/src/Api/Tools/Controllers/SendsController.cs: 299	Attack Vector
	Log_Forging	/src/Api/KeyManagement/Controllers/AccountsKeyManagementController.cs: 37	Attack Vector
	Log_Forging	/src/Api/KeyManagement/Controllers/AccountsKeyManagementController.cs: 37	Attack Vector
	Log_Forging	/src/Api/Vault/Controllers/CiphersController.cs: 220	Attack Vector
	Log_Forging	/src/Api/Auth/Controllers/AuthRequestsController.cs: 87	Attack Vector
	Log_Forging	/src/Api/Auth/Controllers/AuthRequestsController.cs: 75	Attack Vector
	Log_Forging	/src/Api/Auth/Controllers/TwoFactorController.cs: 406	Attack Vector

Fixed Issues

Severity	Issue	Source File / Package
	CSRF	/src/Billing/Controllers/RecoveryController.cs: 38
	CSRF	/src/Api/Controllers/PushController.cs: 38
	CSRF	/src/Billing/Controllers/StripeController.cs: 164
	CSRF	/src/Api/Controllers/PushController.cs: 38
	CSRF	/src/Api/Controllers/PushController.cs: 38
	Privacy_Violation	/src/Api/Auth/Models/Request/Accounts/SetPasswordRequestModel.cs: 28
	Privacy_Violation	/src/Core/Auth/Services/Implementations/AuthRequestService.cs: 208
	Privacy_Violation	/src/Api/AdminConsole/Controllers/OrganizationAuthRequestsController.cs: 59
	Privacy_Violation	/src/Api/AdminConsole/Controllers/OrganizationAuthRequestsController.cs: 59
	Log_Forging	/src/Api/AdminConsole/Controllers/ProvidersController.cs: 72
	Log_Forging	/src/Api/AdminConsole/Controllers/ProvidersController.cs: 72
	Log_Forging	/src/Billing/Controllers/RecoveryController.cs: 38
	Log_Forging	/src/Billing/Controllers/RecoveryController.cs: 38
	Log_Forging	/src/Api/AdminConsole/Controllers/ProvidersController.cs: 72
	Log_Forging	/src/Api/Auth/Controllers/EmergencyAccessController.cs: 159
	Log_Forging	/src/Api/AdminConsole/Controllers/ProvidersController.cs: 72
	Log_Forging	/src/Billing/Controllers/StripeController.cs: 164
	Log_Forging	/src/Billing/Controllers/StripeController.cs: 164
	Log_Forging	/src/Api/Auth/Controllers/AccountsController.cs: 261

[Patrick-Pimentel-Bitwarden]

👍