Added .gitignore

.gitignore

@@ -0,0 +1,105 @@
+```gitignore
+# =========================================================
+# STM32 / CubeIDE build output
+# =========================================================
+Debug/
+Release/
+build/
+Build/
+out/
+
+*.o
+*.obj
+*.d
+*.su
+*.elf
+*.axf
+*.map
+*.hex
+*.bin
+*.list
+
+# CubeIDE autogenerated temp / cache
+.metadata/
+
+# Keep project files tracked
+# .project
+# .cproject
+
+# Ignore only user-specific launch/debug temp
+*.launch
+*.log
+
+# Optional: user-specific settings only
+.settings/*.log
+.settings/language.settings.xml
+
+# =========================================================
+# KiCad generated temporary / backup files
+# =========================================================
+*.kicad_prl
+*.kicad_sch-bak
+*.kicad_pcb-bak
+*.bak
+*-bak
+*.tmp
+
+# Autosave / lock files
+*.autosave
+*.lock
+
+# Plot / manufacturing outputs
+gerbers/
+plot/
+*.gbr
+*.drl
+*.gko
+*.gbl
+*.gtl
+*.gts
+*.gto
+*.gm1
+*.csv
+*.rpt
+*.pos
+*.step
+*.stp
+
+# 3D exports if generated
+exports/
+
+# =========================================================
+# IDE / editor files
+# =========================================================
+.vscode/
+*.swp
+*~
+*.user
+
+# =========================================================
+# OS junk
+# =========================================================
+Thumbs.db
+Desktop.ini
+.DS_Store
+
+# =========================================================
+# Python helper scripts temp
+# =========================================================
+__pycache__/
+*.pyc
+
+# =========================================================
+# Coverage / test artifacts
+# =========================================================
+coverage/
+*.gcda
+*.gcno
+*.gcov
+
+# =========================================================
+# Debugger files
+# =========================================================
+*.jlink
+*.jlinkscript
+```