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>

json-patch/Cargo.toml

@@ -0,0 +1,27 @@
+[package]
+name = "json-patch"
+version = "0.2.7-alpha.0"
+authors = ["Ivan Dubrov <dubrov.ivan@gmail.com>"]
+categories = []
+keywords = ["json", "json-patch"]
+description = "RFC 6902, JavaScript Object Notation (JSON) Patch"
+repository = "https://github.com/idubrov/json-patch"
+license = "MIT/Apache-2.0"
+readme = "README.md"
+edition = "2018"
+
+[features]
+default = ["diff"]
+nightly = []
+diff = []
+
+[dependencies]
+imbl-value = "0.4.1"
+json-ptr = { path = "../json-ptr" }
+serde = { version = "1", features = ["derive"] }
+
+[dev-dependencies]
+rand = "0.9.1"
+serde_json = { version = "1.0.60", features = ["preserve_order"] }
+proptest = "1"
+imbl-value = { version = "0.4.1", features = ["arbitrary"] }