fix: Add directory context to Rust build functions

- Fix build_zinit to cd to correct component directory
- Add proper working directory logging
- Fix branch names for ThreeFold components
- Prepare for successful Rust compilation

Dockerfile

@@ -1,7 +1,7 @@
 # Zero OS Alpine Initramfs Builder Container
 FROM alpine:3.22
 
-# Install build dependencies
+# Install build dependencies including proper musl toolchain
 RUN apk add --no-cache \
     build-base \
     rust \
@@ -16,6 +16,7 @@ RUN apk add --no-cache \
     binutils \
     linux-headers \
     musl-dev \
+    musl-utils \
     pkgconfig \
     openssl-dev \
     bash \
@@ -24,8 +25,11 @@ RUN apk add --no-cache \
     sed \
     coreutils
 
-# Install musl-dev for Rust musl targeting (Alpine handles this differently than rustup)
-RUN apk add --no-cache musl-dev
+# Create musl-gcc wrapper (Alpine's gcc already targets musl)
+RUN echo '#!/bin/sh' > /usr/bin/musl-gcc && \
+    echo 'exec gcc -static "$@"' >> /usr/bin/musl-gcc && \
+    chmod +x /usr/bin/musl-gcc && \
+    which musl-gcc
 
 # Create non-root user for builds matching host user
 RUN adduser -D -s /bin/bash builder