zig-api: export uapi_safe_path_default C ABI symbol from process.zig

Adds uapi_safe_path_default(path_ptr, path_len) as a C-ABI export of
the existing safePathDefault() function, enabling pre-built libzig_api
consumers (e.g. lol-gateway) to call the proven-backed path gate without
a direct Zig module import.

Adds matching declaration to generated/abi/zig_api.h.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: hyperpolymath

zig-api/ffi/zig/src/process.zig

@@ -108,6 +108,19 @@ pub fn safePathDefault(path: []const u8) bool {
     return !result.value;
 }
 
+/// C ABI export of safePathDefault for consumers that link libzig_api as a
+/// pre-built static/shared library and cannot import process.zig directly.
+///
+/// `path_ptr` — pointer to the path bytes (need not be null-terminated).
+/// `path_len` — byte length of the path.
+///
+/// Returns 1 (true) when the path is safe, 0 (false) when denied.
+/// Matches the declaration in generated/abi/zig_api.h: uapi_safe_path_default.
+pub export fn uapi_safe_path_default(path_ptr: [*]const u8, path_len: usize) callconv(.c) u8 {
+    const path = path_ptr[0..path_len];
+    return if (safePathDefault(path)) 1 else 0;
+}
+
 // =============================================================================
 // ExecOutput — captured stdout / stderr from a subprocess
 // =============================================================================

zig-api/generated/abi/zig_api.h

@@ -117,6 +117,25 @@ void uapi_teardown(void);
 #define UAPI_METHOD_OPTIONS          5
 #define UAPI_METHOD_PATCH            6
 
+/* ============================================================================
+ * Path safety  (ffi/zig/src/process.zig)
+ * ========================================================================== */
+
+/**
+ * Check whether a path is safe to open.
+ *
+ * Applies two gates:
+ *   1. Allowlist prefix check (see process.zig DEFAULT_ALLOWLIST).
+ *   2. proven_path_has_traversal — formally-verified traversal detection.
+ *
+ * `path_ptr` — pointer to path bytes (need not be null-terminated).
+ * `path_len` — byte length of the path.
+ *
+ * Returns 1 when the path is safe, 0 when denied.
+ * Fails closed: returns 0 on any proven internal error.
+ */
+uint8_t uapi_safe_path_default(const uint8_t *path_ptr, uint32_t path_len);
+
 /* ============================================================================
  * Gnosis API server  (ffi/zig/src/gnosis.zig)
  * ========================================================================== */