[PM-27098] Add plurals for times

[KatherineInCode]

🎟️ Tracking

https://bitwarden.atlassian.net/browse/PM-27098

📔 Objective

This migrates our time words (hours, days, weeks, seconds) into a stringsdict so we can do proper pluralization. Along the way, some additional enums and code was migrated to BitwardenKit, as they were shared between the apps.

This uses some parts of #1999, but not all of it, to provide a more-focused PR for time-related plurals.

⏰ 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]

Checkmarx One – Scan Summary & Details – 30da93a3-40a3-4d18-bfd0-1f4f19c0c596

Great job! No new security vulnerabilities introduced in this pull request

[codecov]

Codecov Report

❌ Patch coverage is 94.23077% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 82.96%. Comparing base (d6cd64f) to head (575244e).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...ult/AuthenticatorItem/AuthenticatorItemState.swift	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2052      +/-   ##
==========================================
- Coverage   85.31%   82.96%   -2.35%     
==========================================
  Files        1691     1985     +294     
  Lines      144372   161149   +16777     
==========================================
+ Hits       123168   133700   +10532     
- Misses      21204    27449    +6245     

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