cli: fix all compiler warnings and remove dead code

- remove unused helper functions (BuildCommand, TestsCommand, UpdateCommand)
- fix sign-conversion in termios handling
- fix FNV-1a hash sign conversion
- fix variable shadowing in DirectScriptRunner
- clarify logical conditions with explicit parentheses in error rules
- improve overall code safety and determinism

Author: GaspardKirira

src/commands/BuildCommand.cpp

@@ -1496,40 +1496,6 @@ namespace vix::commands::BuildCommand
       process::Plan plan_{};
     };
 
-    static std::optional<fs::path> find_last_built_binary()
-    {
-      namespace fs = std::filesystem;
-
-      const fs::path meta = fs::current_path() / ".vix" / "meta.json";
-
-      if (!fs::exists(meta))
-        return std::nullopt;
-
-      std::ifstream f(meta);
-      if (!f)
-        return std::nullopt;
-
-      std::string content((std::istreambuf_iterator<char>(f)),
-                          std::istreambuf_iterator<char>());
-
-      const std::string key = "\"last_binary\":\"";
-      auto pos = content.find(key);
-      if (pos == std::string::npos)
-        return std::nullopt;
-
-      pos += key.size();
-      auto end = content.find("\"", pos);
-      if (end == std::string::npos)
-        return std::nullopt;
-
-      fs::path p = content.substr(pos, end - pos);
-
-      if (fs::exists(p))
-        return p;
-
-      return std::nullopt;
-    }
-
   } // namespace
 
   int run(const std::vector<std::string> &args)

src/commands/TestsCommand.cpp

@@ -290,13 +290,6 @@ namespace
     return std::nullopt;
   }
 
-  static bool has_flag(
-      const std::vector<std::string> &args,
-      const std::string &flag)
-  {
-    return std::find(args.begin(), args.end(), flag) != args.end();
-  }
-
   static std::string resolve_preset_name(const vix::commands::TestsCommand::detail::Options &opt)
   {
     if (auto p = value_after_flag(opt.forwarded, "--preset"))

src/commands/UpdateCommand.cpp

@@ -238,24 +238,6 @@ namespace vix::commands
       return 0;
     }
 
-    bool lock_contains_dependency_id(const json &lock, const std::string &wantedId)
-    {
-      if (!lock.contains("dependencies") || !lock["dependencies"].is_array())
-      {
-        return false;
-      }
-
-      for (const auto &d : lock["dependencies"])
-      {
-        if (d.value("id", "") == wantedId)
-        {
-          return true;
-        }
-      }
-
-      return false;
-    }
-
     std::string read_locked_version(const json &lock, const std::string &id)
     {
       if (!lock.contains("dependencies") || !lock["dependencies"].is_array())

src/commands/run/RunProcess.cpp

@@ -1015,7 +1015,7 @@ namespace vix::commands::RunCommand::detail
         struct termios tty{};
         if (::tcgetattr(slaveFd, &tty) == 0)
         {
-          tty.c_lflag &= ~ECHO;
+          tty.c_lflag &= static_cast<tcflag_t>(~ECHO);
           ::tcsetattr(slaveFd, TCSANOW, &tty);
         }
       }

src/commands/run/detail/DirectScriptRunner.cpp

@@ -110,8 +110,9 @@ namespace vix::commands::RunCommand::detail
       constexpr std::uint64_t prime = 1099511628211ull;
 
       std::uint64_t h = offset;
-      for (unsigned char c : input)
+      for (char ch : input)
       {
+        const auto c = static_cast<unsigned char>(ch);
         h ^= static_cast<std::uint64_t>(c);
         h *= prime;
       }
@@ -265,9 +266,9 @@ namespace vix::commands::RunCommand::detail
         if (const auto pch = find_vix_pch())
           cmd << " -include-pch " << process::quote(pch->string());
 
-        if (const auto lib = find_vix_lib())
+        if (const auto vixLib = find_vix_lib())
         {
-          cmd << " " << process::quote(lib->string());
+          cmd << " " << process::quote(vixLib->string());
         }
         else
         {
@@ -277,8 +278,8 @@ namespace vix::commands::RunCommand::detail
 #ifndef __APPLE__
             cmd << " -Wl,--start-group";
 #endif
-            for (const auto &lib : libs)
-              cmd << " " << process::quote(lib.string());
+            for (const auto &moduleLib : libs)
+              cmd << " " << process::quote(moduleLib.string());
 #ifndef __APPLE__
             cmd << " -Wl,--end-group";
 #endif

src/errors/runtime/IteratorInvalidationRule.cpp

@@ -41,9 +41,9 @@ namespace vix::cli::errors::runtime
              icontains(log, "attempt to dereference a singular iterator") ||
              icontains(log, "attempt to increment a singular iterator") ||
              icontains(log, "attempt to compare a singular iterator") ||
-             icontains(log, "vector iterator") && icontains(log, "invalid") ||
-             icontains(log, "deque iterator") && icontains(log, "invalid") ||
-             icontains(log, "list iterator") && icontains(log, "invalid");
+             (icontains(log, "vector iterator") && icontains(log, "invalid")) ||
+             (icontains(log, "deque iterator") && icontains(log, "invalid")) ||
+             (icontains(log, "list iterator") && icontains(log, "invalid"));
     }
 
     bool handle(

src/errors/template/ConceptConstraintFailureRule.cpp

@@ -73,7 +73,7 @@ namespace vix::cli::errors::template_rules
 
       return icontains(m, "constraints not satisfied") ||
              icontains(m, "constraint failure") ||
-             icontains(m, "concept") && icontains(m, "not satisfied") ||
+             (icontains(m, "concept") && icontains(m, "not satisfied")) ||
              icontains(m, "requirements not satisfied") ||
              icontains(m, "does not satisfy") ||
              icontains(m, "failed requirement");

src/errors/template/RequiresExpressionFailureRule.cpp

@@ -75,7 +75,7 @@ namespace vix::cli::errors::template_rules
              (icontains(m, "requires") && icontains(m, "invalid")) ||
              icontains(m, "required expression") ||
              icontains(m, "required type") ||
-             icontains(m, "required from here") && icontains(m, "requires") ||
+             (icontains(m, "required from here") && icontains(m, "requires")) ||
              icontains(m, "would be invalid") ||
              icontains(m, "does not satisfy return-type-requirement");
     }

src/errors/template/TemplateArgumentMismatchRule.cpp

@@ -72,7 +72,7 @@ namespace vix::cli::errors::template_rules
       const std::string &m = err.message;
 
       return icontains(m, "wrong number of template arguments") ||
-             icontains(m, "template argument") && icontains(m, "invalid") ||
+             (icontains(m, "template argument") && icontains(m, "invalid")) ||
              icontains(m, "type/value mismatch at argument") ||
              icontains(m, "expected a type, got") ||
              icontains(m, "expected a constant of type") ||