fix: avoid substring denies in audit path keywords (#16243)

## Summary

   Fixes #15944.

   The plugin audit deny-list matched `secret`, `cert`, and
 `conf` as substrings of every path component. This blocked
 valid imports during plugin capability execution, for example
 `numpy/__config__.py`, because `conf` appeared inside the
 module filename.

   This PR changes deny keyword matching to use whole path
 components instead of substring matches. It keeps the
 intended protections for sensitive locations and config
 files, while allowing dependency and stdlib modules whose
 names merely contain those strings.

   ## Changes

   - Match denied path keywords as whole components instead of
 substrings.
   - Keep denying sensitive directory names such as:
     - `secret`
     - `secrets`
     - `cert`
     - `certs`
     - `certificate`
     - `certificates`
     - `conf`
     - `config`
   - Keep denying config files by extension:
     - `.conf`
     - `.ini`
   - Allow legitimate Python module/package paths such as:
     - `numpy/__config__.py`
     - `numpy/_core/_ufunc_config.py`
     - `configparser.py`
     - `sysconfig.py`
     - `logging/config.py`
     - `certifi/cacert.pem`
   - Include the denied target and reason in `PermissionError`
 messages when the audit hook blocks an operation.
   - Remove an unused `<memory>` include from
 `PluginAuditManager.hpp`.

   ## Why

   The previous substring matching caused false positives for
 common dependency and standard-library paths. It also made
 failures hard to diagnose because the Python exception did
 not include the refused path.

   The new behavior is narrower: it blocks sensitive path
 components and config file extensions without treating
 unrelated names like `__config__.py`, `configparser.py`,
 `Conference`, or `Concert` as secrets.

   ## Testing

   - Added/updated unit coverage in
 `tests/slic3rutils/test_plugin_audit.cpp` for:
     - whole-component keyword matches
     - `.conf` / `.ini` blocking
     - case-insensitive matching
     - false-positive paths from #15944

Plugin used for testing:

[orca_audit_numpy_config_repro.py](https://github.com/user-attachments/files/33143848/orca_audit_numpy_config_repro.py)

src/slic3r/plugin/PluginAuditManager.cpp

@@ -351,8 +351,20 @@ std::vector<std::string> PluginAuditManager::default_denied_path_keywords()
     // must never be able to reach a secret, a certificate, or a configuration file just because
     // it happens to live inside an otherwise-allowed root (e.g. the bundled TLS client cert at
     // resources_dir()/cert/..., which would become reachable the moment resources_dir() is
-    // granted as a read-only allowed root).
-    return {"secret", "cert", "conf"};
+    // granted as a read-only allowed root). Match as whole path components, not substrings, so
+    // imports such as numpy/__config__.py and stdlib configparser.py remain usable.
+    return {"secret", "secrets", "cert", "certs", "certificate", "certificates", "conf", "config"};
+}
+
+static bool has_denied_config_extension(std::string name)
+{
+    const size_t stream_pos = name.find(':');
+    if (stream_pos != std::string::npos)
+        name.erase(stream_pos);
+
+    const boost::filesystem::path path(name);
+    const std::string extension = path.extension().string();
+    return extension == ".conf" || extension == ".ini";
 }
 
 bool PluginAuditManager::is_denied_path_keyword(const boost::filesystem::path& candidate) const
@@ -377,7 +389,7 @@ bool PluginAuditManager::is_denied_path_keyword(const boost::filesystem::path& c
             continue;
         std::transform(name.begin(), name.end(), name.begin(), [](unsigned char c) { return std::tolower(c); });
         for (const auto& keyword : m_denied_path_keywords) {
-            if (name.find(keyword) != std::string::npos)
+            if (name == keyword || (keyword == "conf" && has_denied_config_extension(name)))
                 return true;
         }
     }
@@ -810,7 +822,8 @@ bool persist_permission(const std::string&        plugin_key,
 
 int report_denied(PluginAuditManager&            mgr,
                   const std::string&             event_name,
-                  const AuditDecision&           decision)
+                  const AuditDecision&           decision,
+                  const std::string&             target = {})
 {
     AuditViolation violation;
     violation.plugin_key = mgr.current_plugin();
@@ -818,7 +831,13 @@ int report_denied(PluginAuditManager&            mgr,
     violation.reason     = decision.reason;
     mgr.report_violation(violation);
 
-    PyErr_SetString(PyExc_PermissionError, "Plugin attempted an audited operation without permission");
+    std::string message = "Plugin attempted audited operation \"" + event_name + "\" without permission";
+    if (!decision.reason.empty())
+        message += ": " + decision.reason;
+    if (!target.empty())
+        message += ": " + target;
+
+    PyErr_SetString(PyExc_PermissionError, message.c_str());
     return -1;
 }
 
@@ -987,7 +1006,7 @@ int PluginAuditManager::audit_hook(const char* event, PyObject* args, void* user
     if (fs_category) {
         for (const auto& target : targets) {
             if (mgr->is_denied_path(boost::filesystem::path(target)))
-                return PluginAuditDetail::report_denied(*mgr, event_name, {false, "denied path"});
+                return PluginAuditDetail::report_denied(*mgr, event_name, {false, "denied path"}, target);
         }
     }