Prevent Z3_solver_reset abort after memory_max_size OOM by making reset memory-limit-safe (#10254)

`memory_max_size` OOMs were recoverable at `check_sat` time
(`Z3_L_UNDEF` + error handler), but `Z3_solver_reset` could still
terminate the process with an uncaught `out_of_memory_error`. This
change keeps reset on the C API error-reporting path instead of letting
teardown allocations trip the same hard limit.

- **Reset path hardening**
- `Z3_solver_reset` now performs solver teardown under a temporary
suspension of the global memory cap, then restores the previous cap
afterward.
- This avoids aborts when allocator accounting is still above
`memory_max_size` at reset time.

- **Memory manager support**
- Added `memory::get_max_size()` to snapshot/restore the active cap
precisely.

- **Regression coverage**
- Extended `src/test/memory.cpp` with a focused scenario that trips
`Z3_MEMOUT_FAIL` and then calls `Z3_solver_reset` under a non-throwing
error handler, covering the previously aborting recovery path.

```cpp
struct scoped_memory_limit_reset {
    size_t m_prev_max;
    scoped_memory_limit_reset(): m_prev_max(memory::get_max_size()) {
        memory::set_max_size(0);
    }
    ~scoped_memory_limit_reset() {
        memory::set_max_size(m_prev_max);
    }
} scoped_max_memory;
```

<!-- START COPILOT CODING AGENT SUFFIX -->

- Fixes #10250

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>

src/api/api_solver.cpp

@@ -22,6 +22,7 @@ Revision History:
 #include "util/file_path.h"
 #include "util/scoped_timer.h"
 #include "util/file_path.h"
+#include "util/memory_manager.h"
 #include "ast/ast_pp.h"
 #include "api/z3.h"
 #include "api/api_log_macros.h"
@@ -514,6 +515,15 @@ extern "C" {
         Z3_TRY;
         LOG_Z3_solver_reset(c, s);
         RESET_ERROR_CODE();
+        struct scoped_memory_limit_reset {
+            size_t m_prev_max;
+            scoped_memory_limit_reset(): m_prev_max(memory::get_max_size()) {
+                memory::set_max_size(0);
+            }
+            ~scoped_memory_limit_reset() {
+                memory::set_max_size(m_prev_max);
+            }
+        } scoped_max_memory;
         to_solver(s)->m_solver = nullptr;
         to_solver(s)->m_cmd_context = nullptr;
         if (to_solver(s)->m_pp) to_solver(s)->m_pp->reset();