Update to Zig master (0.17.0-dev.864+3deb86baf)

[Copilot]

Zig master introduced a wave of breaking API changes across the build system and standard library. This updates all build scripts to compile cleanly against 0.17.0-dev.864+3deb86baf and bumps minimum_zig_version accordingly.

std.Build API changes

• b.sysroot removed — passed via --sysroot ./emsdk/upstream/emscripten in Makefile instead
• b.build_root.path.? → b.root.root_dir.path.?
• b.pathFromRoot() → b.root.joinString(b.allocator, path) catch @panic("OOM")
• b.args → run.addPassthruArgs()
• LazyPath.dupe(b) → LazyPath.dupe(b.graph)
• b.dupe() → b.allocator.dupe(u8, ...) (needed where caller mutates the string)
• Compile.addIncludePath / linkLibrary moved to Module — use artifact.root_module.*

std.fs → std.Io migration

Most of std.fs is now under std.Io.Dir. Affected APIs and their call-site changes:

// Before
const cwd = std.fs.cwd();
const dir = try cwd.openDir(path, .{});
try cwd.makePath(path);
const file = try std.fs.openFileAbsolute(path, .{});
file.close();
while (try walker.next()) |entry| { ... }

// After
const cwd = std.Io.Dir.cwd();
const dir = try cwd.openDir(b.graph.io, path, .{});
try cwd.createDirPath(b.graph.io, path);
const file = try std.Io.Dir.openFileAbsolute(b.graph.io, path, .{});
file.close(b.graph.io);
while (try walker.next(b.graph.io)) |entry| { ... }

std.fs.path.* and std.fs.File are aliased via std.Io.Dir.path.* / std.Io.File.

Other

• site/package-lock.json regenerated