Add QA test outputs, build scripts, and Dockerfile validation

- Created `qa-test-output-after-fix.txt` and `qa-test-output.txt` to log results of certificate page authentication tests.
- Added `build.sh` for deterministic backend builds in CI, utilizing `go list` for efficiency.
- Introduced `codeql_scan.sh` for CodeQL database creation and analysis for Go and JavaScript/TypeScript.
- Implemented `dockerfile_check.sh` to validate Dockerfiles for base image and package manager mismatches.
- Added `sourcery_precommit_wrapper.sh` to facilitate Sourcery CLI usage in pre-commit hooks.

backend/internal/database/database.go

@@ -0,0 +1,58 @@
+// Package database handles database connections and migrations.
+package database
+
+import (
+	"database/sql"
+	"fmt"
+	"strings"
+
+	"gorm.io/driver/sqlite"
+	"gorm.io/gorm"
+)
+
+// Connect opens a SQLite database connection with optimized settings.
+// Uses WAL mode for better concurrent read/write performance.
+func Connect(dbPath string) (*gorm.DB, error) {
+	// Add SQLite performance pragmas if not already present
+	dsn := dbPath
+	if !strings.Contains(dsn, "?") {
+		dsn += "?"
+	} else {
+		dsn += "&"
+	}
+	// WAL mode: better concurrent access, faster writes
+	// busy_timeout: wait up to 5s instead of failing immediately on lock
+	// cache: shared cache for better memory usage
+	// synchronous=NORMAL: good balance of safety and speed
+	dsn += "_journal_mode=WAL&_busy_timeout=5000&_synchronous=NORMAL&_cache_size=-64000"
+
+	db, err := gorm.Open(sqlite.Open(dsn), &gorm.Config{
+		// Skip default transaction for single operations (faster)
+		SkipDefaultTransaction: true,
+		// Prepare statements for reuse
+		PrepareStmt: true,
+	})
+	if err != nil {
+		return nil, fmt.Errorf("open database: %w", err)
+	}
+
+	// Configure connection pool
+	sqlDB, err := db.DB()
+	if err != nil {
+		return nil, fmt.Errorf("get underlying db: %w", err)
+	}
+	configurePool(sqlDB)
+
+	return db, nil
+}
+
+// configurePool sets connection pool settings for SQLite.
+// SQLite handles concurrency differently than server databases,
+// so we use conservative settings.
+func configurePool(sqlDB *sql.DB) {
+	// SQLite is file-based, so we limit connections
+	// but keep some idle for reuse
+	sqlDB.SetMaxOpenConns(1)    // SQLite only allows one writer at a time
+	sqlDB.SetMaxIdleConns(1)    // Keep one connection ready
+	sqlDB.SetConnMaxLifetime(0) // Don't close idle connections
+}