Too many refactors in one:

- Allowed adding ephemeral(ish) views and functions
- Moved message_count to a concrete database field
- Moved most proxy logic to a stored procedure
- Moved database files around and refactored schema manager

PluralKit.API/Startup.cs

@@ -86,7 +86,7 @@ namespace PluralKit.API
         // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
         public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         {
-            SchemaService.Initialize();
+            Schemas.Initialize();
 
             if (env.IsDevelopment())
             {