test: add 26 tests for multi-thread safety, db CRUD, concurrency, errors (#442)

* fix: use std::sync::RwLock in MessageTool to avoid runtime panic

The `requires_approval` method is synchronous but was using
`tokio::sync::RwLock` with `.await` which requires blocking the
runtime. This caused a panic:
"Cannot block the current thread from within a runtime"

Changes:
- Replace `tokio::sync::RwLock` with `std::sync::RwLock` for
  `default_channel` and `default_target` fields
- Use `unwrap_or_else(|e| e.into_inner())` to gracefully handle
  poisoned locks (recovers instead of panicking)
- Update all usages from `.read().await` to `.read().unwrap_or_else()`

The locks are short-held (just cloning strings), making std::sync::RwLock
appropriate for sync methods called from async contexts.

Fixes: "Cannot block the current thread from within a runtime" panic
when the LLM tries to send a message via the message tool.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* test: comprehensive testing improvements and fix MessageTool blocking_read panic

Fix tokio::sync::RwLock::blocking_read() panic in MessageTool::requires_approval()
under multi-threaded tokio runtimes by switching to std::sync::RwLock with poison
recovery. Add 26 new tests across 4 tiers:

Tier 1 - Multi-thread runtime safety:
- Fix MessageTool to use std::sync::RwLock instead of tokio::sync::RwLock
- 4 multi-thread tests for MessageTool::requires_approval() scenarios
- 1 multi-thread test for HttpTool credential-dependent approval
- 1 structural test exercising all core tool sync trait methods under multi-thread runtime

Tier 2 - Database CRUD coverage:
- Settings lifecycle (CRUD, bulk ops)
- Tool failure tracking (record, broken list, repair)
- Routine lifecycle (create, get, list, update, delete, runs)
- LLM call recording
- Sandbox job lifecycle (create, get, update, list, mode)
- Job events (save, list, limit)
- Estimation snapshot round-trip

Tier 3 - Concurrency:
- ToolRegistry concurrent register + read under 4-worker runtime

Tier 4 - Error coverage:
- Display tests for all 8 error variants
- From conversion tests for top-level Error enum

Supersedes the fix in PR #411 with the same bug fix plus comprehensive test coverage.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix: remove trailing whitespace in registry.rs

Co-Authored-By: Claude Opus 4.6 <[email protected]>

---------

Co-authored-by: Jerome Revillard <[email protected]>
Co-authored-by: Claude Opus 4.6 <[email protected]>
Co-authored-by: Illia Polosukhin <[email protected]>

tests/tool_schema_validation.rs

@@ -138,3 +138,29 @@ fn shell_tool_schema_is_valid() {
     let errors = validate_tool_schema(&schema, "shell");
     assert!(errors.is_empty(), "shell tool schema errors: {errors:?}");
 }
+
+/// Validates that all core tools work correctly under a multi-threaded tokio runtime.
+/// This catches sync-async boundary bugs like tokio::sync::RwLock::blocking_read()
+/// panicking when called from within a multi-threaded runtime context.
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn all_core_tools_work_in_multi_thread_runtime() {
+    let registry = ToolRegistry::new();
+    registry.register_builtin_tools();
+    registry.register_dev_tools();
+
+    let tools = registry.all().await;
+    assert!(
+        !tools.is_empty(),
+        "registry should have tools after registration"
+    );
+
+    for tool in &tools {
+        // These sync trait methods must not panic in multi-thread runtime
+        let _ = tool.name();
+        let _ = tool.description();
+        let _ = tool.parameters_schema();
+        let _ = tool.requires_approval(&serde_json::json!({}));
+        let _ = tool.requires_sanitization();
+        let _ = tool.domain();
+    }
+}