docs(adr): add layered architecture and Docker strategy ADRs

[nanotaboada]

Summary

• Adds ADR-0008 documenting the three-layer architecture, FastAPI Depends() session injection, functional service style, and ORM/Pydantic model separation
• Adds ADR-0009 documenting the multi-stage Docker build with uv export + pip wheel pre-compilation, offline installation, entrypoint seed scripts, and named volume strategy
• Updates docs/adr/README.md index

Test plan

• ADR files render correctly on GitHub (0008-layered-architecture.md, 0009-docker-and-compose-strategy.md)
• README index links resolve to the new files
• No other files changed

🤖 Generated with Claude Code

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This change is 

Summary by CodeRabbit

• Documentation
  • Added architectural documentation describing the system's layered design structure and patterns.
  • Added deployment documentation outlining containerization and orchestration strategy.
  • Updated Architecture Decision Records index with new entries.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Review profile: CHILL

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Run ID: fdeef0b9-2d22-4eb3-bbd2-ff3e5fe027dc

📥 Commits

Reviewing files that changed from the base of the PR and between 454a397 and 88c6a33.

📒 Files selected for processing (3)

• docs/adr/0008-layered-architecture.md
• docs/adr/0009-docker-and-compose-strategy.md
• docs/adr/README.md

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Walkthrough

Two new Architecture Decision Records (ADRs) were added documenting the project's layered architecture pattern with FastAPI dependency injection and the Docker/Compose deployment strategy. The ADR index was updated to reference both new decisions, dated 2026-04-02 with accepted status.

Changes

Cohort / File(s)

Summary

ADR Documentation docs/adr/0008-layered-architecture.md, docs/adr/0009-docker-and-compose-strategy.md, docs/adr/README.md

Added ADR-0008 documenting three-layer architecture (routes with FastAPI APIRouter, services with business logic, schemas with SQLAlchemy ORM) plus separate models for Pydantic types and databases module for session factory. Added ADR-0009 documenting multi-stage Docker builds with Python 3.13, uv export pinned dependencies, offline wheel installation, and Compose orchestration with storage volume and health checks. Updated ADR index table with both entries.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~5 minutes

Possibly related PRs

• PR #535: Introduces the initial ADR documentation framework (ADRs 0001–0007); this PR extends the same ADR index with ADRs 0008 and 0009 to the established decision record structure.

🚥 Pre-merge checks | ✅ 2

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title follows Conventional Commits format with 'docs:' prefix, is 60 characters (under 80), and clearly describes the main changes: adding two ADR documents about layered architecture and Docker strategy.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch docs/add-architecture-and-docker-adrs

• 🛠️ sync documentation: Commit on current branch
• 🛠️ sync documentation: Create PR
• 🛠️ enforce http error handling: Commit on current branch
• 🛠️ enforce http error handling: Create PR
• 🛠️ idiomatic review: Commit on current branch
• 🛠️ idiomatic review: Create PR
• 🛠️ verify api contract: Commit on current branch
• 🛠️ verify api contract: Create PR

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 100.00%. Comparing base (454a397) to head (88c6a33).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff            @@
##            master      #551   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
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  Files            3         3           
  Lines          114       114           
=========================================
  Hits           114       114           

Components	Coverage Δ
Services	100.00% <ø> (ø)
Routes	100.00% <ø> (ø)

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