feat: modernize build tooling and add CI/CD workflow

Switch to Bun for 2-5x faster frontend builds, implement cargo-chef for
reliable Rust dependency caching, and add Biome for fast code
formatting.

Build system improvements:
- Replace pnpm with Bun for frontend package management
- Add cargo-chef to Dockerfile for better Rust build layer caching
- Update all commands to use bun instead of pnpm

Developer experience:
- Add comprehensive Justfile commands (format, format-check, db)
- Implement automated PostgreSQL Docker setup with random port
allocation
- Add stricter checks (--deny warnings on clippy, --all-features flag)

Code quality:
- Add Biome formatter for 10-100x faster TypeScript/JavaScript
formatting
- Add GitHub Actions CI/CD workflow for automated checks
- Update .dockerignore with comprehensive exclusions
- Format all code with cargo fmt (Rust) and Biome (TypeScript)

All changes maintain backward compatibility and can be tested
incrementally.

src/scraper/mod.rs

@@ -67,7 +67,6 @@ impl ScraperService {
             "Spawned worker tasks"
         );
     }
-
 }
 
 #[async_trait::async_trait]
@@ -104,7 +103,10 @@ impl Service for ScraperService {
         let results = futures::future::join_all(all_handles).await;
         let failed = results.iter().filter(|r| r.is_err()).count();
         if failed > 0 {
-            warn!(failed_count = failed, "Some scraper tasks panicked during shutdown");
+            warn!(
+                failed_count = failed,
+                "Some scraper tasks panicked during shutdown"
+            );
             return Err(anyhow::anyhow!("{} task(s) panicked", failed));
         }