Initial commit: MIKILAB KiCad personal library

Self-contained KiCad library (symbols, footprints, 3D models, docs,
import/check tooling) with no dependency on kicad-personal-library.

- Fixed sym-lib-table/fp-lib-table: single (version 7) header, one entry
  per library, MIKILAB_<name> nicknames, ${KIPRJMOD}-relative URIs
- Resolved the SOT95P280X145-5N footprint collision (TPS7A2012PDBVR vs
  TPS7A2018PDBVR): confirmed byte-identical modulo KiCad's internal
  tedit timestamp, unified into one shared footprint
- Resolved a case-insensitive filename collision between the official
  Diode.kicad_sym and a custom diode.kicad_sym
- Wrapped standalone footprints (ESP32-S31-WROOM-3, IC_TPS63020DSJT,
  SOT95P280X145-5N) into their own .pretty libraries so they're
  actually registered in fp-lib-table
- Fixed broken symbol->footprint references (including one pointing at
  a nonexistent easyeda2kicad library)
- Added scripts/check_library.py, import_component.py, add_component.py,
  import_batch.py, and lib_common.py

legacy/symbols/curtis.lib

@@ -0,0 +1,38 @@
+EESchema-LIBRARY Version 2.3
+#encoding utf-8
+#
+# CEM3320
+#
+DEF CEM3320 U 0 40 Y Y 1 F N
+F0 "U" 0 50 50 H V C CNN
+F1 "CEM3320" 0 -50 50 H V C CNN
+F2 "" 0 0 50 V I C CNN
+F3 "" 0 0 50 V I C CNN
+ALIAS V3320
+$FPLIST
+ IPC_SOIC18P127_1145X1030X265L75X40N
+$ENDFPLIST
+DRAW
+S -1150 400 1150 -400 0 1 0 N
+X IN1 1 -1050 600 200 D 50 50 1 1 I
+X IN2 2 -450 600 200 D 50 50 1 1 I
+X GND 3 -1350 -200 200 R 50 50 1 1 W
+X OUT2 4 -200 -600 200 U 50 50 1 1 O
+X OUT1 5 -600 -600 200 U 50 50 1 1 O
+X BOUT2 6 -150 600 200 D 50 50 1 1 O
+X BOUT1 7 -750 600 200 D 50 50 1 1 O
+X GM_IN 8 1350 -100 200 L 50 50 1 1 I
+X RC_IN 9 1350 -300 200 L 50 50 1 1 I
+X BOUT4 10 1050 600 200 D 50 50 1 1 O
+X OUT4 11 600 -600 200 U 50 50 1 1 O
+X FC_IN 12 -1350 100 200 R 50 50 1 1 I
+X VSS 13 -1350 -300 200 R 50 50 1 1 W
+X VCC 14 -1350 -100 200 R 50 50 1 1 W
+X BOUT3 15 450 600 200 D 50 50 1 1 O
+X OUT3 16 200 -600 200 U 50 50 1 1 O
+X IN3 17 150 600 200 D 50 50 1 1 I
+X IN4 18 750 600 200 D 50 50 1 1 I
+ENDDRAW
+ENDDEF
+#
+#End Library