feat: node property inspector

- Right-click node -> Properties shows details dialog
- Shows: ID, name, class, volume, ports, sample rate, channels,
  format, quantum, rate, device, bus, API, priority
- Backend parses extra PipeWire node props (clock.rate, channels, etc.)
- Node type includes all new fields
- stop() already had the SSE cleanup fix

src/graph_engine.cpp

@@ -97,6 +97,36 @@ static void on_node_info(void *data, const struct pw_node_info *info) {
             if (mute_str) {
                 nobj->node.mute = pw_properties_parse_bool(mute_str);
             }
+
+            // Read additional properties
+            const char *str;
+
+            str = spa_dict_lookup(info->props, "default.clock.rate");
+            if (str) nobj->node.sample_rate = (uint32_t)atoi(str);
+
+            str = spa_dict_lookup(info->props, "default.clock.quantum");
+            if (str) nobj->node.quantum = (uint32_t)atoi(str);
+
+            str = spa_dict_lookup(info->props, "audio.channels");
+            if (str) nobj->node.channels = (uint32_t)atoi(str);
+
+            str = spa_dict_lookup(info->props, "audio.format");
+            if (str) nobj->node.format = str;
+
+            str = spa_dict_lookup(info->props, "device.name");
+            if (str) nobj->node.device_name = str;
+
+            str = spa_dict_lookup(info->props, "device.bus");
+            if (str) nobj->node.device_bus = str;
+
+            str = spa_dict_lookup(info->props, "api.alsa.path");
+            if (str) nobj->node.api = str;
+
+            str = spa_dict_lookup(info->props, "priority.driver");
+            if (str) nobj->node.priority = atoi(str);
+
+            str = spa_dict_lookup(info->props, "node.rate");
+            if (str) nobj->node.rate = (uint32_t)atoi(str);
         }
     }
 

src/graph_types.h

@@ -67,11 +67,24 @@ struct Node {
     float       volume;     // 0.0 - 1.0 (linear)
     bool        mute;
 
+    // Properties
+    uint32_t    sample_rate;
+    uint32_t    channels;
+    std::string format;
+    uint32_t    quantum;
+    uint32_t    rate;
+    std::string device_name;
+    std::string device_bus;
+    std::string api;
+    int         priority;
+
     std::vector<uint32_t> port_ids;  // child port IDs
 
     Node() : id(0), mode(PortMode::None), node_type(NodeType::None),
              mode2(PortMode::None), ready(false), changed(false),
-             volume(1.0f), mute(false) {}
+             volume(1.0f), mute(false),
+             sample_rate(0), channels(0), quantum(0), rate(0),
+             priority(0) {}
 };
 
 struct Link;

src/web_server.cpp

@@ -111,6 +111,15 @@ std::string WebServer::buildGraphJson() const {
              << ",\"node_type\":\"" << nodeTypeStr(n.node_type) << "\""
              << ",\"volume\":" << n.volume
              << ",\"mute\":" << (n.mute ? "true" : "false")
+             << ",\"sample_rate\":" << n.sample_rate
+             << ",\"channels\":" << n.channels
+             << ",\"quantum\":" << n.quantum
+             << ",\"rate\":" << n.rate
+             << ",\"format\":\"" << escapeJson(n.format) << "\""
+             << ",\"device_name\":\"" << escapeJson(n.device_name) << "\""
+             << ",\"device_bus\":\"" << escapeJson(n.device_bus) << "\""
+             << ",\"api\":\"" << escapeJson(n.api) << "\""
+             << ",\"priority\":" << n.priority
              << ",\"port_ids\":[";
         bool first_p = true;
         for (uint32_t pid : n.port_ids) {