bench(deps-go): add comprehensive benchmarks for Go ecosystem

Add criterion benchmarks covering:
- go.mod parsing (small/medium/large files, all directives)
- go.sum lockfile parsing
- Version comparison operations
- Pseudo-version detection
- Module path escaping for proxy API
- Position tracking for LSP features
- Unicode and comment handling

Performance targets documented for LSP latency requirements.

Author: bug-ops

Cargo.lock

@@ -28,3 +28,8 @@ semver.workspace = true
 tokio = { workspace = true, features = ["macros", "rt"] }
 tokio-test.workspace = true
 tempfile.workspace = true
+criterion.workspace = true
+
+[[bench]]
+name = "go_benchmarks"
+harness = false