feat(ipuaro): implement indexer module (v0.3.0)

Add complete indexer infrastructure:
- FileScanner: recursive scanning with gitignore support
- ASTParser: tree-sitter based TS/JS/TSX/JSX parsing
- MetaAnalyzer: complexity metrics, dependency analysis
- IndexBuilder: symbol index and dependency graph
- Watchdog: file watching with chokidar and debouncing

321 tests, 96.38% coverage

packages/ipuaro/tests/fixtures/sample-project/.gitignore

@@ -0,0 +1,2 @@
+ignored-file.ts
+*.log

packages/ipuaro/tests/fixtures/sample-project/package.json

@@ -0,0 +1,4 @@
+{
+    "name": "sample-project",
+    "version": "1.0.0"
+}

packages/ipuaro/tests/fixtures/sample-project/src/index.ts

@@ -0,0 +1,3 @@
+export function main(): void {
+    console.log("Hello")
+}

packages/ipuaro/tests/fixtures/sample-project/src/utils.ts

@@ -0,0 +1,3 @@
+export function add(a: number, b: number): number {
+    return a + b
+}