Phase 39 (first slice): Ollama Cloud adapter on /v1/chat

Second provider wired. /v1/chat now routes by optional `provider`
field: default "ollama" hits local via sidecar, "ollama_cloud"
(or "cloud") hits ollama.com/api/generate directly with Bearer auth.
Key sourced at gateway startup from OLLAMA_CLOUD_KEY env, then
/root/llm_team_config.json (providers.ollama_cloud.api_key), then
OLLAMA_CLOUD_API_KEY env. Config source matches LLM Team convention.

Shape-identical to scenario.ts::generateCloud — same endpoint, same
body, same Bearer auth. Cloud path bypasses sidecar entirely (sidecar
is local-only by design, mirrors TS agent.ts).

Changes:
- crates/gateway/src/v1/ollama_cloud.rs (new, 130 LOC) — reqwest
  client, resolve_cloud_key(), chat() adapter, CloudGenerateBody /
  CloudGenerateResponse wire shapes
- crates/gateway/src/v1/ollama.rs — flatten_messages_public()
  re-export so sibling adapters reuse the shape collapse
- crates/gateway/src/v1/mod.rs — provider field on ChatRequest,
  dispatch match in chat() handler, ollama_cloud_key on V1State
- crates/gateway/src/main.rs — resolves cloud key at startup,
  logs which source provided it
- crates/gateway/Cargo.toml — reqwest 0.12 with rustls-tls

Verified end-to-end after restart:
- provider=ollama → qwen3.5:latest local (~400ms, Phase 38 unchanged)
- provider=ollama_cloud + model=gpt-oss:120b → real 225-word
  technical response in 5.4s, 313 tokens

Tests: 9/9 green (7 from Phase 38 + 2 new for cloud body serialization
and key resolver shape).

Not in this slice: trait extraction (full Phase 39 scope adds
ProviderAdapter trait + OpenRouter adapter + fallback chain logic).
These land next with Phase 40 routing engine on top.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

crates/gateway/src/v1/mod.rs

@@ -12,6 +12,7 @@
 //! adding the alias is one line in Phase 39 when it matters.
 
 pub mod ollama;
+pub mod ollama_cloud;
 
 use axum::{
     Router,
@@ -29,6 +30,9 @@ use tokio::sync::RwLock;
 pub struct V1State {
     pub ai_client: aibridge::client::AiClient,
     pub usage: Arc<RwLock<Usage>>,
+    /// Ollama Cloud bearer token. Loaded at startup via
+    /// `ollama_cloud::resolve_cloud_key()`. None = cloud routes 503.
+    pub ollama_cloud_key: Option<String>,
 }
 
 #[derive(Default, Clone, Serialize)]
@@ -76,6 +80,13 @@ pub struct ChatRequest {
     /// overseer / reasoning-heavy path.
     #[serde(default)]
     pub think: Option<bool>,
+    /// Non-OpenAI extension. Selects the provider adapter. Accepted:
+    ///   - None / "ollama" / "local" → local Ollama via sidecar (default)
+    ///   - "ollama_cloud" / "cloud" → Ollama Cloud direct HTTPS
+    /// Phase 40 adds a routing engine that picks this automatically
+    /// from the model name; Phase 38/39 requires explicit selection.
+    #[serde(default)]
+    pub provider: Option<String>,
 }
 
 #[derive(Serialize)]
@@ -115,9 +126,27 @@ async fn chat(
         tracing::warn!("/v1/chat: stream=true requested but Phase 38 returns non-streaming");
     }
 
-    let resp = ollama::chat(&state.ai_client, &req)
-        .await
-        .map_err(|e| (StatusCode::BAD_GATEWAY, format!("provider: {e}")))?;
+    let provider = req.provider.as_deref().unwrap_or("ollama").to_ascii_lowercase();
+    let resp = match provider.as_str() {
+        "ollama" | "local" | "" => ollama::chat(&state.ai_client, &req)
+            .await
+            .map_err(|e| (StatusCode::BAD_GATEWAY, format!("ollama local: {e}")))?,
+        "ollama_cloud" | "cloud" => {
+            let key = state.ollama_cloud_key.as_deref().ok_or((
+                StatusCode::SERVICE_UNAVAILABLE,
+                "OLLAMA_CLOUD_KEY not configured — set env or populate /root/llm_team_config.json".to_string(),
+            ))?;
+            ollama_cloud::chat(key, &req)
+                .await
+                .map_err(|e| (StatusCode::BAD_GATEWAY, format!("ollama cloud: {e}")))?
+        }
+        other => {
+            return Err((
+                StatusCode::BAD_REQUEST,
+                format!("unknown provider '{other}' — supported: ollama, ollama_cloud"),
+            ));
+        }
+    };
 
     {
         let mut u = state.usage.write().await;