Initial commit

Add Discord Archive Manager project with:
- Entity Framework Core data models for Discord exports
- JSON import service for processing Discord chat exports
- Archive service for managing imported data
- Docker configuration for containerized deployment

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,31 @@
+# Environment files
+.env
+.env.*
+*.local
+
+# Build results
+bin/
+obj/
+[Dd]ebug/
+[Rr]elease/
+x64/
+x86/
+
+# Visual Studio
+.vs/
+*.suo
+*.user
+*.userosscache
+*.sln.docstates
+
+# NuGet
+*.nupkg
+**/packages/*
+!**/packages/build/
+
+# User-specific files
+*.rsuser
+*.suo
+*.user
+*.userosscache
+*.sln.docstates