Fix Family B angle decode + add LR-1FMI model

parse_family_b() dùng sai hệ số góc 0.25°/LSB; theo spec Olei chính hãng
(Olei.LidarSensor/LidarDataBlock.GetAngleDegrees) AngleRaw là 0.01°/LSB.
Sai 25× khiến điểm bị gán nhầm góc → một phòng bị bôi thành vòng tròn trên
RViz. Đã verify với thiết bị thật OLELR-1FMI: sau khi sửa ra 2400 điểm/vòng,
0–359.9°, đúng hình học môi trường.

- Đổi hệ số góc 0.25° → 0.01° trong parse_family_b().
- Bỏ qua block invalid (AngleRaw >= 0xFF00) theo spec.
- Dò ranh giới vòng quay PER-POINT thay vì per-packet (một gói có thể chứa
  >1 vòng), tránh gộp nhiều vòng vào một scan.
- Thêm model LR-1FMI (360°, 0.01°/LSB, ~2400 pts/rev) vào bảng model +
  kModelTable, đặt "1FMI" trước "1F" để khớp đúng chuỗi tên.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

include/lidarlib/config.hpp

@@ -0,0 +1,80 @@
+#pragma once
+#include "lidarlib/lidar.hpp"
+#include <memory>
+#include <string>
+#include <vector>
+
+namespace lidarlib {
+
+// ─── Settings for one lidar ─────────────────────────────────────────────────
+// `name` is the unique key used to match entries across saves (rename = old
+// key removed, new key added) — useful if your GUI reconciles a running set of
+// lidars against an edited config list.
+struct LidarConfig {
+    std::string name      = "lidar";
+    std::string ip        = "0.0.0.0";
+    uint16_t    port      = 2368;
+    std::string model     = "AUTO";   // must match an entry in model_names_for_brand(brand)
+    bool        inverted  = false;    // only applies to brand "OLEI" — SickDriver has no equivalent
+    std::string brand     = "OLEI";   // must match an entry in brand_names() — "OLEI" or "SICK"
+
+    friend bool operator==(const LidarConfig& a, const LidarConfig& b) {
+        return a.name == b.name && a.ip == b.ip && a.port == b.port &&
+               a.model == b.model && a.inverted == b.inverted && a.brand == b.brand;
+    }
+    friend bool operator!=(const LidarConfig& a, const LidarConfig& b) { return !(a == b); }
+};
+
+// Any number of lidars — managed as a list so a consuming app/GUI can
+// add/remove entries freely instead of being locked to a fixed front/rear pair.
+struct Config {
+    std::vector<LidarConfig> lidars = {
+        {"front", "0.0.0.0", 2368, "AUTO", false},
+        {"rear",  "0.0.0.0", 2369, "AUTO", true},
+    };
+};
+
+// Known model name -> ModelConfig (matches the constants in lidar.hpp/sick_lidar.hpp).
+// Returns nullptr if name doesn't match any entry.
+const ModelConfig* model_by_name(const std::string& name);
+
+// Names accepted by model_by_name(), for populating a UI dropdown.
+const std::vector<std::string>& model_names();
+
+// Brand names accepted in LidarConfig::brand ("OLEI", "SICK"), for populating
+// a UI dropdown.
+const std::vector<std::string>& brand_names();
+
+// Subset of model_names() valid for a given brand (e.g. "SICK" -> the
+// MODEL_SICK_* names) — empty if `brand` doesn't match any entry in
+// brand_names(). Used to filter the model dropdown once a brand is picked,
+// and to validate that LidarConfig::model actually belongs to its brand.
+const std::vector<std::string>& model_names_for_brand(const std::string& brand);
+
+// Load config.json at `path`. If the file doesn't exist, returns defaults
+// (and does NOT create the file — caller decides whether to save it).
+Config load_config(const std::string& path);
+
+// Overwrite `path` with `cfg` serialized as JSON.
+void save_config(const std::string& path, const Config& cfg);
+
+// ─── THE single config function ─────────────────────────────────────────────
+// Build a ready-to-open lidar from one LidarConfig. This is the one entry point
+// a GUI/app needs: `brand` selects the transport — exactly "SICK" → TCP, any
+// other value (incl. "OLEI", empty, or an old config without the field) → OLEI
+// UDP. `model` is resolved *for that brand*: a name that is unknown OR belongs
+// to the other brand falls back to the brand's sensible default (MODEL_AUTO for
+// OLEI, MODEL_SICK_TIM571 for SICK), so a mis-paired brand+model can't silently
+// configure the wrong driver. `inverted` applies to OLEI only. Returns a unique
+// handle to the unified Lidar interface — call ->open() then
+// ->recv_scan(out, timeout_ms) to get ScanResult { LaserScan scan; ExtraInfo
+// info; }. Never returns nullptr.
+//
+//   lidarlib::LidarConfig c{"front", "192.168.1.10", 2368, "AUTO", false, "OLEI"};
+//   auto lidar = lidarlib::make_lidar(c);
+//   lidar->open();
+//   lidarlib::ScanResult r;
+//   lidar->recv_scan(r, 1000);   // r.scan = LaserScan, r.info = ExtraInfo
+std::unique_ptr<Lidar> make_lidar(const LidarConfig& cfg);
+
+} // namespace lidarlib