feat: oakengine facade, oaknode/oakrender impls, worker+CLI, app skeleton

- oaknode Rust crate: full implementation (core engine, sequence/
  track/block/footage, traverser, serializer, 43 node behaviors;
  493 tests green)
- oakrender Rust crate: full implementation incl. wgpu backend
  skeleton, ticket arena, worker pool (136 tests green; fixed
  lost-wakeup and ticket ordering races)
- src/facade/rust (oakfacade): 222 oakengine_* exports over the
  module C ABIs (61 tests green); worker_main + real POSIX shm
  frame-slot transport (SpscRingBuffer/FrameSlotPool, wire-compatible
  with engine/render/ipc)
- cli/rust + worker/rust binaries (29 + 29 tests green)
- oakotio: FCPXML import/export (49 tests green)
- oaktask: OTIO/FCPXML format dispatch (90 tests green)
- app/rust: gpui app skeleton — dock panels (viewers/timeline/
  explorer/inspector/node editor), transport, olive themes,
  i18n (en/zh), 37 tests green
- gpui submodule: menu checkmarks, dock ratios, vertical meter,
  CPU-frame viewer surface, drop-frame timecode

cli/rust/Cargo.toml

@@ -0,0 +1,43 @@
+# Oak - Non-Linear Video Editor
+# Copyright (C) 2026 Oak Team
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+[package]
+name = "oak-cli"
+version = "0.1.0"
+edition = "2021"
+description = "Oak Video Editor headless command-line consumer of the liboakengine C ABI facade (Rust)"
+license = "GPL-3.0-or-later"
+
+[[bin]]
+name = "oak-cli"
+path = "src/main.rs"
+
+[dependencies]
+clap = { version = "4", features = ["derive"] }
+
+# oakfacade is where the frozen oakengine_* C ABI exports live (staticlib +
+# rlib). oak-cli is a pure consumer of that facade, so it links the rlib
+# directly. The families this CLI needs (init / project / timeline / render /
+# footage / exporter) are still deferred in the facade
+# (src/facade/rust/src/deferred.rs), so this crate references no oakengine_*
+# symbol yet: the subcommands validate their arguments and report the
+# deferral (src/deferred.rs). The extern declarations in src/ffi.rs mirror
+# the engine headers verbatim and resolve against this rlib the moment a
+# family is wrapped -- no manifest change needed.
+oakfacade = { path = "../../src/facade/rust" }
+
+[profile.release]
+panic = "unwind"