zig-p4: pure-Zig ESP32-P4 toolchain

build.zig generates the linker script and drives Zig's own LLD; tools/image.zig
turns the ELF into a flashable image and tools/{rom,serial}.zig speak the mask
ROM loader over the UART. No CMake, ninja, idf.py, esptool, or external linker.

src/soc.zig is a comptime register model over ESP-IDF's own *_reg.h headers;
src/hal/ adds peripheral sequences; src/io/ implements std.Io for the chip;
src/oracle/ diffs this HAL against ESP-IDF's on the die.

1 files changed, 12 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..bbd963e
--- /dev/null
+++ b/.gitignore
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+# Zig's own build cache. Content-addressed, machine-local, and huge: the
+# tracked snapshot had 1,407 files under .zig-cache/h alone, plus object files
+# of 14-45 MB that jj refused to snapshot at all.
+/.zig-cache/
+
+# `zig build` installs exactly one artefact here (the flashable image, plus the
+# ELF under -Delf). Both are derived from tracked sources.
+/zig-out/
+
+# Scope captures: the .json IS the measurement and stays tracked. The .png is a
+# 1.1 MB screenshot of that same JSON and is referenced by nothing.
+/captures/*.png