refactor: 拆分 gateway 单体为独立 crate，新增 systemd 部署方案

将 gateway 内部的 model-fetch、provider-transport、scheduler-core、
usage-runtime、video-tasks-core 模块提取为独立 crate；重构 gateway
内部模块结构（state/router/cache/data/query 等）；移除大量遗留模块
文件；新增 systemd 二进制部署骨架及相关文档；更新前端 usage 相关
API 和组件。

crates/aether-runtime/Cargo.toml

@@ -9,8 +9,11 @@ description = "Shared runtime/bootstrap helpers for Aether Rust services"
 [dependencies]
 async-stream.workspace = true
 axum = { version = "0.8" }
+chrono.workspace = true
 futures-util.workspace = true
 redis.workspace = true
+serde_json.workspace = true
+sha2.workspace = true
 thiserror.workspace = true
 tokio.workspace = true
 tracing.workspace = true

crates/aether-runtime/src/bootstrap.rs

@@ -2,7 +2,7 @@ use crate::config::ServiceRuntimeConfig;
 use crate::error::RuntimeBootstrapError;
 
 pub fn init_service_runtime(config: ServiceRuntimeConfig) -> Result<(), RuntimeBootstrapError> {
-    crate::tracing::init_tracing(config)?;
+    crate::tracing::init_tracing(config.clone())?;
     crate::metrics::init_metrics(config);
     Ok(())
 }

crates/aether-runtime/src/config.rs

@@ -1,6 +1,6 @@
-use crate::observability::ServiceObservabilityConfig;
+use crate::observability::{FileLoggingConfig, LogDestination, ServiceObservabilityConfig};
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ServiceRuntimeConfig {
     pub service_name: &'static str,
     pub default_log_filter: &'static str,
@@ -21,6 +21,26 @@ impl ServiceRuntimeConfig {
         self
     }
 
+    pub const fn with_log_destination(mut self, log_destination: LogDestination) -> Self {
+        self.observability.log_destination = log_destination;
+        self
+    }
+
+    pub fn with_file_logging(mut self, file_logging: FileLoggingConfig) -> Self {
+        self.observability.file_logging = Some(file_logging);
+        self
+    }
+
+    pub fn with_node_role(mut self, node_role: impl Into<String>) -> Self {
+        self.observability.node_role = Some(node_role.into());
+        self
+    }
+
+    pub fn with_instance_id(mut self, instance_id: impl Into<String>) -> Self {
+        self.observability.instance_id = Some(instance_id.into());
+        self
+    }
+
     pub const fn with_metrics_namespace(mut self, metrics_namespace: &'static str) -> Self {
         self.observability.metrics_namespace = metrics_namespace;
         self

crates/aether-runtime/src/lib.rs

@@ -7,6 +7,7 @@ mod error;
 pub mod metrics;
 mod observability;
 pub mod queue;
+pub mod redaction;
 pub mod shutdown;
 pub mod task;
 mod tracing;
@@ -23,9 +24,14 @@ pub use distributed::{
 };
 pub use error::RuntimeBootstrapError;
 pub use metrics::{prometheus_response, service_up_sample, MetricKind, MetricLabel, MetricSample};
-pub use observability::ServiceObservabilityConfig;
+pub use observability::{
+    FileLoggingConfig, LogDestination, LogRotation, ServiceObservabilityConfig,
+};
 pub use queue::{
     bounded_queue, BoundedQueueReceiver, BoundedQueueSender, QueueSendError, QueueSnapshot,
 };
+pub use redaction::{summarize_text_payload, TextPayloadSummary};
 pub use shutdown::wait_for_shutdown_signal;
-pub use tracing::{init_reloadable_tracing, LogFormat, LogReloader};
+pub use tracing::{
+    init_reloadable_service_tracing, init_reloadable_tracing, LogFormat, LogReloader,
+};

crates/aether-runtime/src/observability.rs

@@ -1,9 +1,57 @@
 use crate::tracing::LogFormat;
+use std::path::PathBuf;
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum LogDestination {
+    Stdout,
+    File,
+    Both,
+}
+
+impl LogDestination {
+    pub const fn needs_file_sink(self) -> bool {
+        matches!(self, Self::File | Self::Both)
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum LogRotation {
+    Hourly,
+    Daily,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct FileLoggingConfig {
+    pub dir: PathBuf,
+    pub rotation: LogRotation,
+    pub retention_days: u64,
+    pub max_files: usize,
+}
+
+impl FileLoggingConfig {
+    pub fn new(
+        dir: impl Into<PathBuf>,
+        rotation: LogRotation,
+        retention_days: u64,
+        max_files: usize,
+    ) -> Self {
+        Self {
+            dir: dir.into(),
+            rotation,
+            retention_days,
+            max_files,
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct ServiceObservabilityConfig {
     pub log_format: LogFormat,
     pub metrics_namespace: &'static str,
+    pub log_destination: LogDestination,
+    pub file_logging: Option<FileLoggingConfig>,
+    pub node_role: Option<String>,
+    pub instance_id: Option<String>,
 }
 
 impl ServiceObservabilityConfig {
@@ -11,6 +59,30 @@ impl ServiceObservabilityConfig {
         Self {
             log_format,
             metrics_namespace,
+            log_destination: LogDestination::Stdout,
+            file_logging: None,
+            node_role: None,
+            instance_id: None,
         }
     }
+
+    pub const fn with_log_destination(mut self, log_destination: LogDestination) -> Self {
+        self.log_destination = log_destination;
+        self
+    }
+
+    pub fn with_file_logging(mut self, file_logging: FileLoggingConfig) -> Self {
+        self.file_logging = Some(file_logging);
+        self
+    }
+
+    pub fn with_node_role(mut self, node_role: impl Into<String>) -> Self {
+        self.node_role = Some(node_role.into());
+        self
+    }
+
+    pub fn with_instance_id(mut self, instance_id: impl Into<String>) -> Self {
+        self.instance_id = Some(instance_id.into());
+        self
+    }
 }

crates/aether-runtime/src/redaction.rs

@@ -0,0 +1,36 @@
+use std::fmt::Write as _;
+
+use sha2::{Digest, Sha256};
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct TextPayloadSummary {
+    pub bytes: usize,
+    pub sha256: String,
+}
+
+pub fn summarize_text_payload(text: &str) -> TextPayloadSummary {
+    let digest = Sha256::digest(text.as_bytes());
+    let mut sha256 = String::with_capacity(digest.len() * 2);
+    for byte in digest {
+        write!(&mut sha256, "{byte:02x}").expect("writing to string should not fail");
+    }
+    TextPayloadSummary {
+        bytes: text.len(),
+        sha256,
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::summarize_text_payload;
+
+    #[test]
+    fn summarizes_text_payload_without_exposing_content() {
+        let summary = summarize_text_payload("secret-body");
+        assert_eq!(summary.bytes, 11);
+        assert_eq!(
+            summary.sha256,
+            "7c3029502007b2beae470d090221f0a8f7708be361be4662f4b649426e5767b3"
+        );
+    }
+}