Add unit tests to fix CI "No tests found" failure

[Copilot]

📝 Description

CI was failing with No tests found, exiting with code 1 — Jest found zero matching test files. Adds 42 unit tests across 4 suites covering the core game logic modules.

🎮 Type of Change

• 🐛 Bug fix (non-breaking change which fixes an issue)
• ✨ New feature (non-breaking change which adds functionality)
• 💥 Breaking change (fix or feature that would cause existing functionality to not work as expected)
• 📚 Documentation update
• ⚡ Performance improvement
• 🎨 Style/UI update
• ♻️ Code refactoring
• 🧪 Test update

🎯 Game Mode Impact

• RTS (Commander View)
• FPS (Field Operative View)
• Both modes
• UI/Menu only
• Backend/Infrastructure

🔍 What Changed?

Added

• src/__tests__/constants.test.ts — validates all exported constants (colors, camera FOV/distances, performance budgets, material properties, physics values, resource names)
• src/__tests__/gameStore.test.ts — covers all useGameStore actions: selectUnit, enterFPS, exitFPS, togglePause, reset; asserts initial state and state transitions
• src/__tests__/resourceStore.test.ts — covers addCredits/Fuel/Power, consumeCredits/Fuel (sufficient and insufficient cases), setPowerConsumption/Production, reset
• src/__tests__/pathfinding.test.ts — covers AStarPathfinder: direct paths, diagonal routing, obstacle avoidance, unreachable goals, same-node paths, y=0 constraint on all nodes

Changed

Fixed

• CI pipeline no longer exits with code 1 due to missing test files

Removed

📸 Screenshots/Videos

N/A

🧪 Testing

How Has This Been Tested?

• Unit tests
• Integration tests
• Manual testing on iOS Simulator
• Manual testing on physical iOS device
• Performance testing

Test Configuration

• Device: N/A
• iOS Version: N/A
• Test Scenario: npm test -- --coverage --maxWorkers=2 — 4 suites, 42 tests, all pass

✅ Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published

🎯 Performance Impact

• FPS Impact: None
• Memory Impact: None
• Build Size Impact: None

📋 Related Issues

Relates to https://github.com/astickleyid/iron-command-ios/actions/runs/21166989269/job/61015583962

📝 Additional Notes

Tests run against existing source without mocks — useGameStore and useResourceStore are exercised via getState() directly (no React renderer needed); AStarPathfinder is instantiated with a small 20×20 grid to keep tests fast.

🎖️ Deployment Notes

No deployment impact.

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By submitting this PR, I confirm that:

• I have read and followed the CONTRIBUTING.md guidelines
• I have tested my changes thoroughly
• I am ready for this PR to be reviewed

Original prompt

Reference: https://github.com/astickleyid/iron-command-ios/actions/runs/21166989269/job/61015583962#step:5:1

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[Copilot]

Pull request overview

Adds Jest unit tests under src/__tests__ to ensure CI no longer fails with “No tests found” and to provide baseline coverage for core game logic modules (constants, Zustand stores, and A* pathfinding).

Changes:

• Added unit tests validating exported config constants (palette, camera, performance, materials, physics, resources).
• Added unit tests for useGameStore and useResourceStore state transitions and reset behavior.
• Added unit tests for AStarPathfinder path generation, obstacle avoidance, and edge cases.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
src/tests/constants.test.ts	Verifies key exported values from src/config/constants.ts to prevent accidental config drift.
src/tests/gameStore.test.ts	Exercises useGameStore initial state and action-driven transitions (RTS/FPS, pause, reset).
src/tests/resourceStore.test.ts	Exercises useResourceStore initial state, add/consume operations, power accounting setters, and reset.
src/tests/pathfinding.test.ts	Validates AStarPathfinder pathfinding behavior across clear routes, obstacles, unreachable goals, and invariants (y=0).