[PROTOTYPE] LogSubject with ECS log format

[audreyality]

🛑 This PR is created to share ideas; it will not be merged.

📔 Objective

This code outlines an imagined LogSubject, which operates like a persistent ReplaySubject.

• It extracts RX, DI, and storage key infrastructure from the UserStateSubject to outline the contours of the type.
• It includes type definitions for select portions of the Elastic Common Schema.

❗ Note ❗
The elastic common schema was used because I'm familiar with it. The schema for a full implementation is an open decision.

⏰ 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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 15.76%. Comparing base (543cf0f) to head (6a9962f).
Report is 12 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (543cf0f) and HEAD (6a9962f). Click for more details.

HEAD has 1 upload less than BASE

Flag	BASE (543cf0f)	HEAD (6a9962f)
	2	1

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #13367       +/-   ##
===========================================
- Coverage   35.20%   15.76%   -19.45%     
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  Files        3126       27     -3099     
  Lines       92563     1884    -90679     
  Branches    16857        0    -16857     
===========================================
- Hits        32590      297    -32293     
+ Misses      57516     1587    -55929     
+ Partials     2457        0     -2457     

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[github-actions]

Checkmarx One – Scan Summary & Details – b4833d15-39b9-41e2-97b5-c4957c52fa08

Great job, no security vulnerabilities found in this Pull Request