fix(release): make the x86_64 musl binary actually static

Routing the x86_64-unknown-linux-musl link through Ubuntu's musl-gcc
wrapper overrode Rust's crt-static default and produced a dynamic
binary with an interpreter of /lib/ld-musl-x86_64.so.1. That path
exists on approximately no machine outside Alpine, so the shipped
binary died at exec time with "required file not found" everywhere —
the opposite of what a musl build is for. aarch64-unknown-linux-musl
never used musl-gcc and was static all along; only x86_64 was broken.

Drop musl-tools and the linker override and let Rust link with its
own bundled musl libc.a, which yields a static-pie executable.

Add a post-build check that fails the release if a musl binary has an
INTERP segment, so this can't silently ship again.

Also correct the asset-URL comment: Gitea serves
/releases/download/latest/<name>, not GitHub's
/releases/latest/download/<name>.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011J8C6eRmWEZsh28vkEMD9H

.gitea/workflows/release.yaml

@@ -133,8 +133,15 @@ jobs:
             # crti.o, and friends needed at link time.
             apt: "gcc-aarch64-linux-gnu libc6-dev-arm64-cross"
             rustflags: "-D warnings"
+          # No musl-tools / musl-gcc here on purpose. Rust ships a
+          # self-contained musl libc.a plus the crt objects for this
+          # target, and the default link mode is static-pie. Routing the
+          # link through Ubuntu's musl-gcc wrapper instead produces a
+          # *dynamic* binary needing /lib/ld-musl-x86_64.so.1, which
+          # exists on approximately no machine outside Alpine — the
+          # opposite of what a musl build is for.
           - target: x86_64-unknown-linux-musl
-            apt: "musl-tools"
+            apt: ""
             rustflags: "-D warnings"
           - target: aarch64-unknown-linux-musl
             apt: ""
@@ -168,13 +175,29 @@ jobs:
       - name: Build nuwiki-ls
         env:
           # Per-target linker overrides. Cargo ignores the entries that
-          # don't match the current target, so setting all of them here
-          # keeps the matrix declarative.
+          # don't match the current target, so setting them here keeps
+          # the matrix declarative. Only add an override for a target
+          # whose default linker genuinely can't do the job.
           CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER: aarch64-linux-gnu-gcc
-          CARGO_TARGET_X86_64_UNKNOWN_LINUX_MUSL_LINKER: musl-gcc
           RUSTFLAGS: ${{ matrix.rustflags }}
         run: cargo build --release --target ${{ matrix.target }} -p nuwiki-ls
 
+      # A musl build only earns its keep if it is actually static. A
+      # dynamic one silently fails at exec time with "no such file or
+      # directory" on every non-Alpine host, so fail the release here
+      # rather than shipping it.
+      - name: Verify musl binary is statically linked
+        if: contains(matrix.target, 'musl')
+        run: |
+          set -euo pipefail
+          bin="target/${{ matrix.target }}/release/nuwiki-ls"
+          if readelf -l "$bin" | grep -q INTERP; then
+            echo "::error::$bin is dynamically linked but should be static:"
+            readelf -l "$bin" | grep -A2 INTERP
+            exit 1
+          fi
+          echo "OK: $bin has no INTERP segment (statically linked)."
+
       - name: Package archive
         id: package
         env:
@@ -183,7 +206,9 @@ jobs:
           set -euo pipefail
           archive="nuwiki-ls-${VERSION}-${{ matrix.target }}.tar.gz"
           tar -czf "$archive" -C "target/${{ matrix.target }}/release" nuwiki-ls
-          # Use a stable name without version so /releases/latest/download/nuwiki-ls-{target}.tar.gz always resolves.
+          # Use a stable name without version so the download URL always
+          # resolves. Note the Gitea shape is /releases/download/latest/<name>,
+          # not GitHub's /releases/latest/download/<name> — the latter 404s.
           stable="nuwiki-ls-${{ matrix.target }}.tar.gz"
           mv "$archive" "$stable"
           echo "archive=$stable" >> "$GITHUB_OUTPUT"