fix(plugins): Python plugins see the host document again

Plugins read the host's document through a shared reference across the
dynamic-library boundary, and the entity index hashed with foldhash's
per-process seed, so every handle lookup from the plugin missed. The
codec now uses a fixed hasher (opencadcodec f385f75; kernel 9841749,
graph e9c23ad).

The Python IPC suite also caught up with intended changes: ATTDEF
renders its tag, DXF now keeps the lock-position flag, and the modify
audit turns associative arrays off since it checks loose copies.
The rate-limiter test waits for the host's check instead of a fixed
sleep that raced on macOS, and ENV_LOCK no longer cascades a poisoned
lock into every later test.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

crates/ocs_web_worker/Cargo.toml

@@ -8,7 +8,7 @@ publish = false
 crate-type = ["cdylib"]
 
 [dependencies]
-codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "d36331d", features = ["serde"] }
+codec = { package = "opencadcodec", git = "https://github.com/HakanSeven12/opencadcodec.git", rev = "f385f75", features = ["serde"] }
 bincode = "1.3"
 serde = { version = "1", features = ["derive"] }
 console_error_panic_hook = "0.1"