docs: add detailed Chinese comments for code files and correct GPIO mapping table in main.md

Hardware/text.kicad_prl

@@ -7,7 +7,7 @@
     "hidden_nets": [
       "GND"
     ],
-    "high_contrast_mode": 1,
+    "high_contrast_mode": 0,
     "net_color_mode": 1,
     "opacity": {
       "images": 0.6,
@@ -33,7 +33,6 @@
     },
     "visible_items": [
       "vias",
-      "footprint_text",
       "footprint_anchors",
       "ratsnest",
       "grid",
@@ -53,7 +52,7 @@
       "board_outline_area",
       "ly_points"
     ],
-    "visible_layers": "ffffffff_ffffffff_ffffffff_ffffffff",
+    "visible_layers": "ffffffff_ffffffff_ffffffff_fffffffb",
     "zone_display_mode": 0
   },
   "git": {