Method init

server/src/server/disk_prefix_cache.cpp:194–211

static void write_u64(FILE * f, uint64_t v) { std::fwrite(&v, 8, 1, f); }
static void write_i64(FILE * f, int64_t v)  { std::fwrite(&v, 8, 1, f); }
static void write_u16(FILE * f, uint16_t v) { std::fwrite(&v, 2, 1, f); }

static bool read_u32(FILE * f, uint32_t & out) { return std::fread(&out, 4, 1, f) == 1; }
static bool read_u64(FILE * f, uint64_t & out) { return std::fread(&out, 8, 1, f) == 1; }
static bool read_i64(FILE * f, int64_t & out)  { return std::fread(&out, 8, 1, f) == 1; }
static bool read_u16(FILE * f, uint16_t & out) { return std::fread(&out, 2, 1, f) == 1; }

// ─── Construction ───────────────────────────────────────────────────────

DiskPrefixCache::DiskPrefixCache(const DiskCacheConfig & cfg, ModelBackend & backend)
    : config_(cfg), backend_(backend) {}

// ─── Initialization ─────────────────────────────────────────────────────

bool DiskPrefixCache::init() {
    if (disabled()) return true;

    if (!mkdir_p(config_.cache_dir)) {
        std::fprintf(stderr, "[disk-cache] failed to create dir: %s\n",
                     config_.cache_dir.c_str());
        return false;