feat: Add OpaClient to wrap auth checks

[tpoliaw]

Proof of concept opa client with dependency injection and example check

[codecov]

Codecov Report

❌ Patch coverage is 56.17978% with 39 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.32%. Comparing base (62353cd) to head (b98b3b3).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/blueapi/service/authorization.py	53.19%	22 Missing ⚠️
src/blueapi/service/main.py	54.05%	17 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1541      +/-   ##
==========================================
- Coverage   95.35%   94.32%   -1.03%     
==========================================
  Files          43       44       +1     
  Lines        3205     3297      +92     
==========================================
+ Hits         3056     3110      +54     
- Misses        149      187      +38     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.