Add coordinate validation and ESLint integration

- Add explicit latitude/longitude validation in location submissions
- Implement ESLint with TypeScript support and flat config
- Auto-fix 621 formatting issues across codebase
- Add comprehensive tests for coordinate validation
- Update documentation with lint scripts and validation rules
- Maintain 128 passing tests with enhanced security

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

tests/unit/models/Location.test.ts

@@ -138,7 +138,7 @@ describe('Location Model', () => {
 
       // Check that we have all locations and they're ordered by created_at DESC
       expect(allLocations).toHaveLength(3);
-      
+
       // The query uses ORDER BY created_at DESC, so the most recent should be first
       // Since they're created in the same moment, check that ordering is consistent
       expect(allLocations[0]).toHaveProperty('id');

tests/unit/services/DatabaseService.test.ts

@@ -5,7 +5,7 @@ describe('DatabaseService', () => {
 
   beforeEach(() => {
     databaseService = new DatabaseService();
-    
+
     // Mock console methods to reduce test noise
     jest.spyOn(console, 'log').mockImplementation(() => {});
     jest.spyOn(console, 'error').mockImplementation(() => {});
@@ -88,7 +88,7 @@ describe('DatabaseService', () => {
     it('should allow multiple instances', () => {
       const service1 = new DatabaseService();
       const service2 = new DatabaseService();
-      
+
       expect(service1).toBeInstanceOf(DatabaseService);
       expect(service2).toBeInstanceOf(DatabaseService);
       expect(service1).not.toBe(service2);

tests/unit/services/ProfanityFilterService.test.ts

@@ -27,10 +27,10 @@ describe('ProfanityFilterService', () => {
 
     it('should load custom words during initialization', async () => {
       await profanityWordModel.create('customword', 'high', 'test');
-      
+
       const newFilter = new ProfanityFilterService(profanityWordModel);
       await newFilter.initialize();
-      
+
       expect(newFilter.containsProfanity('customword')).toBe(true);
     });
   });
@@ -50,7 +50,7 @@ describe('ProfanityFilterService', () => {
       // Test basic profanity detection - may or may not be case insensitive
       const testWord = 'damn';
       expect(profanityFilter.containsProfanity(testWord)).toBe(true);
-      
+
       // Test with sentences containing profanity
       expect(profanityFilter.containsProfanity('This is DAMN cold')).toBe(true);
       expect(profanityFilter.containsProfanity('What the HELL')).toBe(true);
@@ -104,7 +104,7 @@ describe('ProfanityFilterService', () => {
     it('should determine severity levels correctly', () => {
       const lowResult = profanityFilter.analyzeProfanity('damn');
       const mediumResult = profanityFilter.analyzeProfanity('shit');
-      
+
       expect(lowResult.severity).toBe('low');
       expect(mediumResult.severity).toBe('medium');
     });
@@ -164,7 +164,7 @@ describe('ProfanityFilterService', () => {
 
     it('should remove custom words', async () => {
       const added = await profanityFilter.addCustomWord('removeme', 'low', 'test');
-      
+
       const result = await profanityFilter.removeCustomWord(added.id);
 
       expect(result.deleted).toBe(true);
@@ -180,7 +180,7 @@ describe('ProfanityFilterService', () => {
 
     it('should update custom words', async () => {
       const added = await profanityFilter.addCustomWord('updateme', 'low', 'test');
-      
+
       const result = await profanityFilter.updateCustomWord(added.id, {
         word: 'updated',
         severity: 'high',
@@ -208,14 +208,14 @@ describe('ProfanityFilterService', () => {
   describe('text normalization', () => {
     it('should normalize text correctly', () => {
       const normalized = profanityFilter.normalizeText('Hello   World!!!');
-      
+
       expect(typeof normalized).toBe('string');
       expect(normalized.length).toBeGreaterThan(0);
     });
 
     it('should handle special characters', () => {
       const normalized = profanityFilter.normalizeText('h3ll0 w0rld');
-      
+
       expect(normalized).toContain('hello world');
     });
 
@@ -228,13 +228,13 @@ describe('ProfanityFilterService', () => {
   describe('severity and category helpers', () => {
     it('should get severity for words', () => {
       const severity = profanityFilter.getSeverity('damn');
-      
+
       expect(['low', 'medium', 'high']).toContain(severity);
     });
 
     it('should get category for words', () => {
       const category = profanityFilter.getCategory('damn');
-      
+
       expect(typeof category).toBe('string');
       expect(category.length).toBeGreaterThan(0);
     });
@@ -242,7 +242,7 @@ describe('ProfanityFilterService', () => {
     it('should return default values for unknown words', () => {
       const severity = profanityFilter.getSeverity('unknownword');
       const category = profanityFilter.getCategory('unknownword');
-      
+
       expect(['low', 'medium', 'high']).toContain(severity);
       expect(typeof category).toBe('string');
     });
@@ -251,26 +251,26 @@ describe('ProfanityFilterService', () => {
   describe('utility methods', () => {
     it('should get all words', () => {
       const words = profanityFilter.getAllWords();
-      
+
       expect(Array.isArray(words)).toBe(true);
       expect(words.length).toBeGreaterThan(0);
     });
 
     it('should get severity level as number', () => {
       const level = profanityFilter.getSeverityLevel();
-      
+
       expect(typeof level).toBe('number');
     });
 
     it('should get severity name', () => {
       const name = profanityFilter.getSeverityName();
-      
+
       expect(typeof name).toBe('string');
     });
 
     it('should have close method', () => {
       expect(typeof profanityFilter.close).toBe('function');
-      
+
       // Should not throw
       profanityFilter.close();
     });