Add WASM fallbacks for tree-sitter and SQLite, fix installer

Replace native tree-sitter with web-tree-sitter + tree-sitter-wasms for
universal cross-platform support. Add node-sqlite3-wasm as a fallback
when better-sqlite3 native bindings aren't available. Move better-sqlite3
and sqlite-vss to optionalDependencies so installs never fail.

Fix installer to use npx fallback when global npm install fails, so MCP
config, hooks, and quick-start instructions all work without the bare
codegraph command in PATH.

Fix tests: update schema version expectation, fix db test paths and
method names, extract MAX_OUTPUT_LENGTH as module constant, normalize
Windows path separators in import resolver.

package.json

@@ -34,11 +34,12 @@
   "license": "MIT",
   "dependencies": {
     "@xenova/transformers": "^2.17.0",
-    "better-sqlite3": "^11.0.0",
     "commander": "^14.0.2",
     "figlet": "^1.8.0",
+    "node-sqlite3-wasm": "^0.8.30",
     "picomatch": "^4.0.3",
-    "tree-sitter": "0.22.4"
+    "tree-sitter-wasms": "^0.1.11",
+    "web-tree-sitter": "^0.25.3"
   },
   "devDependencies": {
     "@types/better-sqlite3": "^7.6.0",
@@ -49,26 +50,10 @@
     "vitest": "^2.1.9"
   },
   "optionalDependencies": {
-    "@sengac/tree-sitter-dart": "1.1.6",
-    "sqlite-vss": "^0.1.2",
-    "tree-sitter-c": "0.23.2",
-    "tree-sitter-c-sharp": "0.23.1",
-    "tree-sitter-cpp": "0.23.4",
-    "tree-sitter-go": "0.23.4",
-    "tree-sitter-java": "0.23.5",
-    "tree-sitter-javascript": "0.23.1",
-    "tree-sitter-kotlin": "0.3.8",
-    "tree-sitter-php": "0.23.11",
-    "tree-sitter-python": "0.23.4",
-    "tree-sitter-ruby": "0.23.1",
-    "tree-sitter-rust": "0.23.1",
-    "tree-sitter-swift": "0.6.0",
-    "tree-sitter-typescript": "0.23.2"
+    "better-sqlite3": "^11.0.0",
+    "sqlite-vss": "^0.1.2"
   },
   "engines": {
     "node": ">=18.0.0"
-  },
-  "overrides": {
-    "tree-sitter": "0.22.4"
   }
 }