add tree-sitter syntax highlighting via dart:ffi

Vendor libtree-sitter.so (v0.26.8, wasmtime 44.0 statically linked)
and call its C API through dart:ffi. Grammar WASM files are loaded by
tree-sitter's embedded wasmtime engine via ts_wasm_store_load_language.

48 grammars compiled with tree-sitter build --wasm, 48 highlight
queries (42 from upstream repos, 6 written in-house for comment,
erlang, gdscript, gitignore, hcl, hlsl, swift). SQLite grammar
replaces full SQL (974K-line parser exhausted RAM at compile time).

Removes wasm_run and wasm_run_flutter — they downloaded a 22 MB
binary from GitHub at first launch, violating the no-network-on-
default-launch-path policy.

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

Makefile

@@ -46,7 +46,7 @@ ifeq ($(APP_PRESENT),yes)
 	@bin/clide --daemon & echo $$! > $(DAEMON_PID_FILE)
 	@echo "Daemon PID $$(cat $(DAEMON_PID_FILE))"
 	@echo "Launching Flutter app…"
-	-cd app && flutter run -d linux
+	-cd app && LD_LIBRARY_PATH=$(CURDIR)/app/native/linux-x64$${LD_LIBRARY_PATH:+:$$LD_LIBRARY_PATH} flutter run -d linux
 	@$(MAKE) --no-print-directory stop
 else
 	@echo "(pubspec.yaml not scaffolded yet; skipping)"