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>

app/assets/queries/sqlite.scm

@@ -0,0 +1,179 @@
+;;;
+
+";" @punctuation.delimiter
+"," @punctuation.delimiter
+"." @punctuation.delimiter
+
+"(" @punctuation.bracket
+")" @punctuation.bracket
+
+[
+    "||"
+    "~" "&" "|" "<<" ">>"
+    "+" "-" "*" "/" "%"
+    "=" "==" "!=" "<>" ">" ">=" "<" "<="
+    "->" "->>"
+] @operator
+
+;;;
+
+(signed_number) @number
+
+(numeric_literal) @number
+(string_literal) @string
+(blob_literal) @string.special
+(identifier) @constant
+(bind_parameter) @variable.parameter
+(comment) @comment
+
+;;;
+
+(ABORT) @keyword
+(ACTION) @keyword
+(ADD) @keyword
+(AFTER) @keyword
+(ALL) @keyword
+(ALTER) @keyword
+(ALWAYS) @keyword
+(ANALYZE) @keyword
+(AND) @keyword
+(AS) @keyword
+(ASC) @keyword
+(ATTACH) @keyword
+(AUTOINCREMENT) @keyword
+(BEFORE) @keyword
+(BEGIN) @keyword
+(BETWEEN) @keyword
+(BY) @keyword
+(CASCADE) @keyword
+(CASE) @keyword
+(CAST) @keyword
+(CHECK) @keyword
+(COLLATE) @keyword
+(COLUMN) @keyword
+(COMMIT) @keyword
+(CONFLICT) @keyword
+(CONSTRAINT) @keyword
+(CREATE) @keyword
+(CROSS) @keyword
+(CURRENT) @keyword
+(CURRENT_DATE) @keyword
+(CURRENT_TIME) @keyword
+(CURRENT_TIMESTAMP) @keyword
+(DATABASE) @keyword
+(DEFAULT) @keyword
+(DEFERRABLE) @keyword
+(DEFERRED) @keyword
+(DELETE) @keyword
+(DESC) @keyword
+(DETACH) @keyword
+(DISTINCT) @keyword
+(DO) @keyword
+(DROP) @keyword
+(EACH) @keyword
+(ELSE) @keyword
+(END) @keyword
+(ESCAPE) @keyword
+(EXCEPT) @keyword
+(EXCLUDE) @keyword
+(EXCLUSIVE) @keyword
+(EXISTS) @keyword
+(EXPLAIN) @keyword
+(FAIL) @keyword
+(FALSE) @keyword
+(FILTER) @keyword
+(FIRST) @keyword
+(FOLLOWING) @keyword
+(FOR) @keyword
+(FOREIGN) @keyword
+(FROM) @keyword
+(GENERATED) @keyword
+(GLOB) @keyword
+(GROUP) @keyword
+(GROUPS) @keyword
+(HAVING) @keyword
+(IF) @keyword
+(IGNORE) @keyword
+(IMMEDIATE) @keyword
+(IN) @keyword
+(INDEX) @keyword
+(INDEXED) @keyword
+(INITIALLY) @keyword
+(INNER) @keyword
+(INSERT) @keyword
+(INSTEAD) @keyword
+(INTERSECT) @keyword
+(INTO) @keyword
+(IS) @keyword
+(ISNULL) @keyword
+(JOIN) @keyword
+(KEY) @keyword
+(LAST) @keyword
+(LEFT) @keyword
+(LIKE) @keyword
+(LIMIT) @keyword
+(MATCH) @keyword
+(MATERIALIZED) @keyword
+(NATURAL) @keyword
+(NO) @keyword
+(NOT) @keyword
+(NOTHING) @keyword
+(NOTNULL) @keyword
+(NULL) @keyword
+(NULLS) @keyword
+(OF) @keyword
+(OFFSET) @keyword
+(ON) @keyword
+(OR) @keyword
+(ORDER) @keyword
+(OTHERS) @keyword
+(OUTER) @keyword
+(OVER) @keyword
+(PARTITION) @keyword
+(PLAN) @keyword
+(PRAGMA) @keyword
+(PRECEDING) @keyword
+(PRIMARY) @keyword
+(QUERY) @keyword
+(RAISE) @keyword
+(RANGE) @keyword
+(RECURSIVE) @keyword
+(REFERENCES) @keyword
+(REGEXP) @keyword
+(REINDEX) @keyword
+(RELEASE) @keyword
+(RENAME) @keyword
+(REPLACE) @keyword
+(RESTRICT) @keyword
+(RETURNING) @keyword
+(ROLLBACK) @keyword
+(ROW) @keyword
+(ROWID) @keyword
+(ROWS) @keyword
+(SAVEPOINT) @keyword
+(SELECT) @keyword
+(SET) @keyword
+(STORED) @keyword
+(TABLE) @keyword
+(TEMP) @keyword
+(TEMPORARY) @keyword
+(THEN) @keyword
+(TIES) @keyword
+(TO) @keyword
+(TRANSACTION) @keyword
+(TRIGGER) @keyword
+(TRUE) @keyword
+(UNBOUNDED) @keyword
+(UNION) @keyword
+(UNIQUE) @keyword
+(UPDATE) @keyword
+(USING) @keyword
+(VACUUM) @keyword
+(VALUES) @keyword
+(VIEW) @keyword
+(VIRTUAL) @keyword
+(WHEN) @keyword
+(WHERE) @keyword
+(WINDOW) @keyword
+(WITH) @keyword
+(WITHOUT) @keyword