feat: make policy length limits configurable per engine (#624)

- Add PolicyLengthConfig struct with max_col, max_file_bytes, and
  max_lines fields, replacing hardcoded constants in the lexer.
- Add Engine::set_policy_length_config and clear_policy_length_config
  to allow callers to override the default limits.
- Add Source::from_contents_with_limits and from_file_with_limits for
  direct Source construction with custom limits; existing from_contents
  and from_file signatures are preserved using defaults.
- Add tests for default rejection, custom limits, and engine plumbing.
- Add bindings for C, C++, Python, WASM/JS, Java, Ruby, C#, Go

bindings/java/Test.java

@@ -2,6 +2,7 @@
 // Licensed under the MIT License.
 
 import com.microsoft.regorus.Engine;
+import com.microsoft.regorus.PolicyLengthConfig;
 import com.microsoft.regorus.PolicyModule;
 import com.microsoft.regorus.Program;
 import com.microsoft.regorus.Rvm;
@@ -26,6 +27,9 @@ public class Test {
             // Enable coverage.
             engine.setEnableCoverage(true);
 
+            // Raise the default col limit to 2000
+            engine.setPolicyLengthConfig(new PolicyLengthConfig(2000, 1048576, 20000));
+
             // Evaluate rule.
             String valueJson = engine.evalRule("data.test.message");
             System.out.println(valueJson);