test: add direct unit test for ProjectRepository

[dmccoystephenson]

Summary

• A new ProjectRepositoryTest is added under src/test/java/com/preponderous/parpt/repo/, constructing ProjectRepository directly with a Mockito-mocked ProjectJsonReaderWriter (no Spring context, no filesystem).
• Each behaviour listed in Add a direct unit test for ProjectRepository #51 is asserted directly:
  • the constructor seeds the in-memory list from readJson() and does not write;
  • findAll() returns a defensive copy;
  • add(...) on a duplicate name throws NameTakenException, leaves the list unchanged and never calls writeJson;
  • remove(...) on an unknown name throws ProjectNotFoundException (message asserted) and never calls writeJson;
  • successful add, remove and clear each persist exactly once, with the persisted contents asserted.
• findByName hit/miss cases are also covered.
• Because writeJson receives the repository's own mutable list, each call's contents are snapshotted in a doAnswer so that the assertions reflect the list at call time rather than at verification time.
• Characterization only; no production code is changed.

Test plan

• ./gradlew test -Dorg.gradle.java.home=/usr/lib/jvm/java-21-openjdk-amd64: 114 tests executed, 0 failures, 0 errors (9 in ProjectRepositoryTest), counted from build/test-results/test/*.xml
• CI (Build and Test, CI Pipeline) green on this branch

Deferred issues (skip reasons)

• Add installation script for Linux #36 (Linux install script): new packaging/distribution surface, larger than this test-expansion cycle.
• Save data to user's home directory by default #33 (save data to home directory): changes the persisted-data path in application.yaml, a do-not-auto-merge path that needs a human decision.
• Add controller endpoints to create, retrieve, update and delete projects #27 (REST controller endpoints): a large new feature surface (web layer) outside this cycle's scope ceiling.
• Update command #21 (update command): a feature cycle in its own right; deferred in favour of the tiebreaker-preferred test expansion.
• Input validation w/ Jakarta #8 (Jakarta input validation): needs a build.gradle dependency change (do-not-auto-merge path).

Closes #51

This PR description was drafted during a Gardener session (https://github.com/Stephenson-Software/gardener).

🤖 Generated with Claude Code

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drafted by Claude on behalf of Daniel Stephenson

[github-actions]

Test Results

114 tests  +9   114 ✅ +9   1s ⏱️ ±0s
 18 suites +1     0 💤 ±0 
 18 files   +1     0 ❌ ±0 

Results for commit a40ad59. ± Comparison against base commit a4a8205.

♻️ This comment has been updated with latest results.

[dmccoystephenson]

Self-review rubric (head a40ad59):

• Scope: PASS — gh pr diff 53 --name-only lists only src/test/java/com/preponderous/parpt/repo/ProjectRepositoryTest.java; no production, formatting or doc churn.
• Tests-new: PASS — no new public production methods; every public ProjectRepository method (findAll, clear, add, remove, findByName, constructor) is now exercised directly by at least one test.
• Tests-fix: N/A — no bug fix. As an empirical substitute, findAll() was temporarily mutated to return projects; locally: findAll_ShouldReturnDefensiveCopy FAILED (1 of 9), then PASSED after the mutation was reverted. So the defensive-copy assertion is observable rather than vacuous.
• Sibling structure: PASS — follows MarkdownFormatterTest (@ExtendWith(MockitoExtension.class), @Mock, @BeforeEach construction) and the repo package's AssertJ plus methodName_ShouldExpectedBehavior naming from ProjectJsonReaderWriterImplTest.
• Sibling renames: N/A — nothing renamed.
• Docs: PASS — README/CONTRIBUTING describe commands and ./gradlew test; neither is affected by a new test class.
• Issue resolution: PASS — all five bullets in Add a direct unit test for ProjectRepository #51 are asserted (seeding, defensive copy, duplicate-name no-write, unknown-name no-write, exactly-once writeJson for add/remove/clear).
• CI / manual validation: PASS — ./gradlew test on JDK 21 locally executed 114 tests, 0 failures, 0 errors (from build/test-results/test/*.xml), and build (21), test and Test Results are green on the PR head.
• Shell command tests / Round-trip coverage / I/O behind an interface: N/A — no command, domain field or I/O code is touched.

Findings:

• src/test/java/com/preponderous/parpt/repo/ProjectRepositoryTest.java:15 — a redundant import static org.mockito.ArgumentMatchers.anyList; (already covered by Mockito.*) was found and removed in a40ad59.
• src/test/java/com/preponderous/parpt/repo/ProjectRepositoryTest.java:37 — the writeJson stub is lenient() because the constructor, duplicate-name, unknown-name and findByName tests never write; under strict stubs these tests would otherwise fail with UnnecessaryStubbingException. This is intentional.
• Out of diff: ProjectRepository's constructor stores the list returned by readJson() without copying it, so it relies on ProjectJsonReaderWriterImpl returning a mutable list. The test stubs a mutable ArrayList to match current behaviour; no production change is proposed in this characterization cycle.

Characterization-only PR; ready to merge once no further review comments arrive.

This review was drafted during a Gardener session (https://github.com/Stephenson-Software/gardener).

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drafted by Claude on behalf of Daniel Stephenson