Fix build break (#634)

* fix: update bindings and builtins for breaking dependency upgrades

- Update rand 0.10 API: use RngExt trait instead of removed Rng trait
- Update jsonschema 0.45 API: replace removed BasicOutput/apply with
  iter_errors for schema validation
- Update jni 0.22 API: migrate from deprecated JNIEnv to EnvUnowned
  with_env pattern, replace deprecated get_string/new_string/throw
  methods with their modern equivalents
- Update pyo3 0.28 API: replace removed PyObject with Py<PyAny>,
  deprecated downcast with cast, and removed with_gil with attach

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* ci(dependabot): create per-dependency PRs for Cargo updates

Remove the groups.rust-dependencies catch-all group so Dependabot
opens a separate PR for each Cargo dependency update instead of
bundling them all into a single PR.

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* fix: enable getrandom wasm_js feature for wasm32-unknown-unknown builds

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

* fix: address PR review comments

- Stream iter_errors directly into BTreeSet without intermediate Vec
- Use JNI_TRUE/JNI_FALSE for jboolean instead of bool coercion

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

---------

Signed-off-by: Anand Krishnamoorthi <anakrish@microsoft.com>

src/schema/meta.rs

@@ -38,13 +38,12 @@ pub fn validate_schema(schema: &serde_json::Value) -> bool {
 /// Validates a schema definition against the Regorus meta-schema.
 /// Returns Ok(()) if valid, or Err with validation errors if invalid.
 pub fn validate_schema_detailed(schema: &serde_json::Value) -> Result<(), Vec<String>> {
-    if let jsonschema::BasicOutput::Invalid(errors) = META_SCHEMA_VALIDATOR.apply(schema).basic() {
-        let msgs: alloc::collections::BTreeSet<String> = errors
-            .iter()
-            .map(|e| format!("{}: {}", e.instance_location(), e.error_description()))
-            .collect();
-        let msgs: Vec<String> = msgs.into_iter().collect();
-        return Err(msgs);
+    let msgs: alloc::collections::BTreeSet<String> = META_SCHEMA_VALIDATOR
+        .iter_errors(schema)
+        .map(|e| format!("{}: {}", e.instance_path(), e))
+        .collect();
+    if !msgs.is_empty() {
+        return Err(msgs.into_iter().collect());
     }
 
     Ok(())