introduce the virtual filesystem everywhere

this unfortunately means I had to cut some features (bye bye commit history! for now)
stuff's not quite 100% working just yet (like branch links, which were and are still broken)
we also don't have content_version impls just yet

Cargo.lock

@@ -1545,20 +1545,6 @@ version = "0.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c20c8dbed6283a09604c3e69b4b7eeb54e298b8a600d4d5ecb5ad39de609f1d0"
 
-[[package]]
-name = "tower-livereload"
-version = "0.9.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61d6cbbab4b2d3cafd21fb211cc4b06525a0df919c3e8ca3d36485b1c1bd4cd4"
-dependencies = [
- "bytes",
- "http",
- "http-body",
- "pin-project-lite",
- "tokio",
- "tower",
-]
-
 [[package]]
 name = "tower-service"
 version = "0.3.2"
@@ -1611,7 +1597,6 @@ dependencies = [
  "serde_json",
  "tokio",
  "toml_edit",
- "tower-livereload",
  "treehouse-format",
  "ulid",
  "url",