Fixes 2 Bugs and 13 Compiler Warnings (#10670)

* fixes: %g directive writing between 1 and 13 bytes into a region of size between 6 and 18 [-Wformat-overflow=]

* fixes: %5s directive writing between 5 and 63 bytes into a region of size 58 [-Wformat-overflow=]

* fixes: catching polymorphic type by value [-Wcatch-value=]

* fixes: [-Wcomment]; removes whitespaces

* increases buffer size from 71B to 90B to avoid potential ovfl.

src/libslic3r/AppConfig.cpp

@@ -883,7 +883,7 @@ std::string AppConfig::load()
                 }
             }
         }
-    } catch(std::exception err) {
+    } catch(const std::exception &err) {
         BOOST_LOG_TRIVIAL(info) << format("parse app config \"%1%\", error: %2%", AppConfig::loading_path(), err.what());
 
         return err.what();

src/libslic3r/Fill/FillRectilinear.cpp

@@ -3576,7 +3576,7 @@ Polylines FillLateralHoneycomb::fill_surface(const Surface *surface, const FillP
     //     |
     //     |
     // 0 --+--
-    //    / \
+    //    ⟋ ⟍
     // why inverted?
     // it makes determining some of the properties easier
     // and the two angled legs provide additional horizontal stiffness

src/libslic3r/Format/STEP.cpp

@@ -712,7 +712,7 @@ unsigned int Step::get_triangle_num(double linear_deflection, double angle_defle
                 return 0;
             }
         }
-    } catch(Exception e) {
+    } catch(const Exception &e) {
         return 0;
     }
     

src/libslic3r/GCode.cpp

@@ -5511,7 +5511,7 @@ LayerResult GCode::process_layer(
     // add tag for processor
     gcode += ";" + GCodeProcessor::reserved_tag(GCodeProcessor::ETags::Layer_Change) + "\n";
     // export layer z
-    char buf[64];
+    char buf[80];
     sprintf(buf, print.is_BBL_printer() ? "; Z_HEIGHT: %g\n" : ";Z:%g\n", print_z);
     gcode += buf;
     // export layer height