feat(runtime): replace tokio+reqwest with asupersync async runtime

- Add HTTP adapter layer (src/http.rs) wrapping asupersync h1 client
- Migrate gitlab client, graphql, and ollama to HTTP adapter
- Swap entrypoint from #[tokio::main] to RuntimeBuilder::new().block_on()
- Rewrite signal handler for asupersync (RuntimeHandle::spawn + ctrl_c())
- Migrate rate limiter sleeps to asupersync::time::sleep(wall_now(), d)
- Add asupersync-native HTTP integration tests
- Convert timeline_seed_tests to RuntimeBuilder pattern

Phases 1-3 of asupersync migration (atomic: code won't compile without all pieces).

src/app/handlers.rs

@@ -162,6 +162,7 @@ async fn handle_ingest(
     robot_mode: bool,
     quiet: bool,
     metrics: &MetricsLayer,
+    rt_handle: &asupersync::runtime::RuntimeHandle,
 ) -> Result<(), Box<dyn std::error::Error>> {
     let start = std::time::Instant::now();
     let dry_run = args.dry_run && !args.no_dry_run;
@@ -212,7 +213,7 @@ async fn handle_ingest(
     let recorder = SyncRunRecorder::start(&recorder_conn, &command, run_id_short)?;
 
     let signal = ShutdownSignal::new();
-    install_ctrl_c_handler(signal.clone());
+    install_ctrl_c_handler(rt_handle, signal.clone());
 
     let ingest_result: std::result::Result<(), Box<dyn std::error::Error>> = async {
         match args.entity.as_deref() {
@@ -1516,6 +1517,7 @@ async fn handle_embed(
     config_override: Option<&str>,
     args: EmbedArgs,
     robot_mode: bool,
+    rt_handle: &asupersync::runtime::RuntimeHandle,
 ) -> Result<(), Box<dyn std::error::Error>> {
     use std::sync::Arc;
     use std::sync::atomic::{AtomicBool, Ordering};
@@ -1526,7 +1528,7 @@ async fn handle_embed(
     let retry_failed = args.retry_failed && !args.no_retry_failed;
 
     let signal = ShutdownSignal::new();
-    install_ctrl_c_handler(signal.clone());
+    install_ctrl_c_handler(rt_handle, signal.clone());
 
     let embed_bar = lore::cli::progress::nested_progress("Embedding", 0, robot_mode);
     let bar_clone = embed_bar.clone();
@@ -1565,6 +1567,7 @@ async fn handle_sync_cmd(
     args: SyncArgs,
     robot_mode: bool,
     metrics: &MetricsLayer,
+    rt_handle: &asupersync::runtime::RuntimeHandle,
 ) -> Result<(), Box<dyn std::error::Error>> {
     let dry_run = args.dry_run && !args.no_dry_run;
 
@@ -1671,7 +1674,7 @@ async fn handle_sync_cmd(
     // Skip the normal recorder setup and let the dispatch handle everything.
     if options.is_surgical() {
         let signal = ShutdownSignal::new();
-        install_ctrl_c_handler(signal.clone());
+        install_ctrl_c_handler(rt_handle, signal.clone());
 
         let start = std::time::Instant::now();
         match run_sync(&config, options, None, &signal).await {
@@ -1695,7 +1698,7 @@ async fn handle_sync_cmd(
     let recorder = SyncRunRecorder::start(&recorder_conn, "sync", run_id_short)?;
 
     let signal = ShutdownSignal::new();
-    install_ctrl_c_handler(signal.clone());
+    install_ctrl_c_handler(rt_handle, signal.clone());
 
     let start = std::time::Instant::now();
     match run_sync(&config, options, Some(run_id_short), &signal).await {