audit fixes, repo restructure, and documentation

Soundness and performance audit (17 fixes):
- See AUDIT.md for full details and @claude comments in code

Repo restructure:
- Inline json-ptr and json-patch submodules as regular directories
- Remove cbor submodule, replace serde_cbor with ciborium
- Rename patch-db/ -> core/, patch-db-macro/ -> macro/,
  patch-db-macro-internals/ -> macro-internals/, patch-db-util/ -> util/
- Purge upstream CI/CD, bench, and release cruft from json-patch
- Remove .gitmodules

Test fixes:
- Fix proptest doesnt_crash (unique file paths, proper close/cleanup)
- Add PatchDb::close() for clean teardown

Documentation:
- Add README.md, ARCHITECTURE.md, CONTRIBUTING.md, CLAUDE.md, AUDIT.md
- Add TSDocs to TypeScript client exports

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

util/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "patch-db-util"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+clap = "3.2.16"
+patch-db = { path = "../core", features = ["debug"] }
+serde_json = "1.0.85"
+tokio = { version = "1.20.1", features = ["full"] }

util/src/main.rs

@@ -0,0 +1,43 @@
+use patch_db::json_ptr::{JsonPointer, PtrSegment, ROOT};
+use serde_json::Value;
+
+#[tokio::main]
+async fn main() {
+    let mut app = clap::App::new("patch-db-util")
+        .subcommand(
+            clap::Command::new("dump").arg(
+                clap::Arg::new("PATH")
+                    .required(true)
+                    .help("Path to the database file"),
+            ),
+        )
+        .subcommand(
+            clap::Command::new("from-dump").arg(
+                clap::Arg::new("PATH")
+                    .required(true)
+                    .help("Path to the database file"),
+            ),
+        );
+
+    match app.clone().get_matches().subcommand() {
+        Some(("dump", matches)) => {
+            let path = matches.value_of("PATH").unwrap();
+            let db = patch_db::PatchDb::open(path).await.unwrap();
+            let dump = db.dump(&ROOT).await;
+            serde_json::to_writer_pretty(&mut std::io::stdout(), &dump.value).unwrap();
+            println!();
+        }
+        Some(("from-dump", matches)) => {
+            let path = matches.value_of("PATH").unwrap();
+            let value: Value = serde_json::from_reader(&mut std::io::stdin()).unwrap();
+            let db = patch_db::PatchDb::open(path).await.unwrap();
+            db.put(
+                &JsonPointer::<&str, (&[PtrSegment], &[PtrSegment])>::default(),
+                &value,
+            )
+            .await
+            .unwrap();
+        }
+        _ => app.print_long_help().unwrap(),
+    }
+}