feat(setup): quick onboarding, preserve .env vars, clean up boot logging (#821)

* feat(setup): quick onboarding, preserve .env vars, clean up boot logging (#751, #674)

- Add upsert_bootstrap_vars() to preserve user-added .env vars on re-onboarding
- Add --quick mode: auto-defaults DB + security, asks only LLM provider (2 steps)
- Auto-triggered onboarding uses quick mode for near-instant first run
- Fix NEAR AI model fetch to use cloud-api.near.ai when API key is set
- Handle missing WASM tools/channels directories gracefully
- Downgrade all boot/shutdown tracing::info! to debug (boot screen shows user output)

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix(setup): gate env_backend variable behind postgres feature flag [skip-regression-check]

Clippy lint fix — not a behavioral change, just moving a variable declaration
inside the cfg(feature = "postgres") block where it's used.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix(review): address PR review comments

- WASM loaders: use tokio::fs::metadata, only treat NotFound as empty,
  propagate other IO errors, handle TOCTOU in read_dir
- bootstrap: only ignore NotFound in read_to_string, propagate other errors
- wizard: restore print_info/print_success for migrations in interactive
  mode (gated by !config.quick), keep tracing::debug for diagnostics
- tests: use shared crate::config::helpers::ENV_MUTEX instead of separate
  NEARAI_ENV_MUTEX to prevent cross-test env var races
- README: fix quick mode description to mention model selection, clarify
  auto_setup_database may prompt when DATABASE_URL is set

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* feat(setup): skip prompts for DATABASE_URL in quick mode [skip-regression-check]

auto_setup_database() now uses DATABASE_URL directly without calling
step_database_postgres() (which prompts for confirmation). Quick mode
should be fully non-interactive when env vars are already set.

Co-Authored-By: Claude Opus 4.6 <[email protected]>

* fix(cli): update --quick help text to mention model selection [skip-regression-check]

Co-Authored-By: Claude Opus 4.6 <[email protected]>

---------

Co-authored-by: Claude Opus 4.6 <[email protected]>

src/channels/manager.rs

@@ -75,7 +75,7 @@ impl ChannelManager {
                     break;
                 }
             }
-            tracing::info!(channel = %name, "Hot-added channel stream ended");
+            tracing::debug!(channel = %name, "Hot-added channel stream ended");
         });
 
         Ok(())
@@ -92,7 +92,7 @@ impl ChannelManager {
         for (name, channel) in channels.iter() {
             match channel.start().await {
                 Ok(stream) => {
-                    tracing::info!("Started channel: {}", name);
+                    tracing::debug!("Started channel: {}", name);
                     streams.push(stream);
                 }
                 Err(e) => {

src/channels/wasm/loader.rs

@@ -184,18 +184,32 @@ impl WasmChannelLoader {
     /// └── telegram.capabilities.json
     /// ```
     pub async fn load_from_dir(&self, dir: &Path) -> Result<LoadResults, WasmChannelError> {
-        if !dir.is_dir() {
-            return Err(WasmChannelError::Io(std::io::Error::new(
-                std::io::ErrorKind::NotADirectory,
-                format!("{} is not a directory", dir.display()),
-            )));
+        match fs::metadata(dir).await {
+            Ok(meta) if meta.is_dir() => {}
+            Ok(_) => {
+                return Err(WasmChannelError::Io(std::io::Error::new(
+                    std::io::ErrorKind::NotADirectory,
+                    format!("{} is not a directory", dir.display()),
+                )));
+            }
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
+                return Ok(LoadResults::default());
+            }
+            Err(e) => return Err(WasmChannelError::Io(e)),
         }
 
         let mut results = LoadResults::default();
 
         // Collect all .wasm entries first, then load in parallel
         let mut channel_entries = Vec::new();
-        let mut entries = fs::read_dir(dir).await?;
+        // Handle TOCTOU: if read_dir fails with NotFound, treat as empty
+        let mut entries = match fs::read_dir(dir).await {
+            Ok(entries) => entries,
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => {
+                return Ok(LoadResults::default());
+            }
+            Err(e) => return Err(WasmChannelError::Io(e)),
+        };
 
         while let Some(entry) = entries.next_entry().await? {
             let path = entry.path();
@@ -486,4 +500,21 @@ mod tests {
         let result = loader.load_from_files("", &wasm_path, None).await;
         assert!(result.is_err());
     }
+
+    #[tokio::test]
+    async fn load_from_dir_returns_empty_when_dir_missing() {
+        let config = WasmChannelRuntimeConfig::for_testing();
+        let runtime = Arc::new(WasmChannelRuntime::new(config).unwrap());
+        let loader = WasmChannelLoader::new(runtime, Arc::new(PairingStore::new()), None);
+
+        let dir = TempDir::new().unwrap();
+        let missing = dir.path().join("nonexistent_channels_dir");
+
+        let results = loader.load_from_dir(&missing).await;
+
+        // Must succeed with empty results, not error
+        let results = results.expect("missing dir should return Ok, not Err");
+        assert!(results.loaded.is_empty());
+        assert!(results.errors.is_empty());
+    }
 }

src/channels/web/server.rs

@@ -370,7 +370,7 @@ pub async fn start_server(
         if let Err(e) = axum::serve(listener, app)
             .with_graceful_shutdown(async {
                 let _ = shutdown_rx.await;
-                tracing::info!("Web gateway shutting down");
+                tracing::debug!("Web gateway shutting down");
             })
             .await
         {

src/channels/webhook_server.rs

@@ -68,7 +68,7 @@ impl WebhookServer {
             if let Err(e) = axum::serve(listener, app)
                 .with_graceful_shutdown(async {
                     let _ = shutdown_rx.await;
-                    tracing::info!("Webhook server shutting down");
+                    tracing::debug!("Webhook server shutting down");
                 })
                 .await
             {