feat(keys): one-paste harness setup — Claude Code, Codex, OpenCode, Continue, Cline

The "connect your app" card in the API-keys view now leads with auto-setup
scripts for popular coding harnesses, each pre-filled with this gateway's URL
and the freshly created key:

  Claude Code — env exports (the gateway speaks Anthropic /v1/messages
      natively; the protocol is now ON by default, and when a config has it
      off the tab shows a warning with a one-click Enable button)
  Codex — appends a [model_providers.cortiq] block to ~/.codex/config.toml
  OpenCode — writes the provider into opencode.json
  Continue — appends the model to ~/.continue/config.yaml
  Cline — the exact values to paste into the extension settings

The gateway also detects which harnesses are already present on its machine
(binaries across PATH + common install dirs, config files under home) via
GET /admin/api/harnesses: installed tabs get a ✓, and the status line under
the snippet says "installed" or "already configured for this gateway" when
the harness config mentions cortiq. Works on Linux/macOS/Windows.

curl / python / javascript SDK snippets stay as before. 16 new strings in
all 7 languages.

src/admin/mod.rs

@@ -160,6 +160,7 @@ pub fn api_routes(admin_token: String) -> Router<SharedState> {
             "/admin/api/protocols",
             get(get_protocols).put(put_protocols),
         )
+        .route("/admin/api/harnesses", get(get_harnesses))
         .route("/admin/api/settings", get(get_settings).put(put_settings))
         .route("/admin/api/keys", get(list_keys).post(create_key))
         .route("/admin/api/keys/:key", axum::routing::delete(delete_key))
@@ -989,6 +990,84 @@ async fn put_routing(State(state): State<SharedState>, Json(body): Json<RoutingB
     ok(json!({ "ok": true }))
 }
 
+// ──────────────────────────── harness detection ────────────────────────────
+// Which coding harnesses are present on the machine the gateway runs on, so the
+// API-keys view can mark tabs "installed" / "already configured for cortiq".
+// Detection is best-effort: binaries in PATH + common install dirs, config
+// files under the user's home. Works on Linux/macOS/Windows.
+
+fn harness_home() -> Option<std::path::PathBuf> {
+    std::env::var_os("HOME")
+        .or_else(|| std::env::var_os("USERPROFILE"))
+        .map(std::path::PathBuf::from)
+}
+
+fn find_bin(name: &str) -> bool {
+    let exts: &[&str] = if cfg!(windows) {
+        &[".exe", ".cmd", ".bat", ""]
+    } else {
+        &[""]
+    };
+    let mut dirs: Vec<std::path::PathBuf> = std::env::var_os("PATH")
+        .map(|p| std::env::split_paths(&p).collect())
+        .unwrap_or_default();
+    if let Some(home) = harness_home() {
+        // GUI-launched processes often miss the shell PATH — add usual suspects
+        for extra in [
+            ".local/bin",
+            ".cargo/bin",
+            "bin",
+            ".bun/bin",
+            ".npm-global/bin",
+            "AppData/Roaming/npm",
+        ] {
+            dirs.push(home.join(extra));
+        }
+    }
+    dirs.extend(["/usr/local/bin", "/opt/homebrew/bin"].map(std::path::PathBuf::from));
+    dirs.iter()
+        .any(|d| exts.iter().any(|e| d.join(format!("{name}{e}")).is_file()))
+}
+
+/// Does the harness config mention cortiq (i.e. was it pointed at this gateway)?
+fn config_mentions_cortiq(rel: &str) -> bool {
+    harness_home()
+        .map(|h| h.join(rel))
+        .and_then(|p| std::fs::read_to_string(p).ok())
+        .map(|c| c.to_lowercase().contains("cortiq"))
+        .unwrap_or(false)
+}
+
+async fn get_harnesses() -> ApiResult {
+    let harnesses = tokio::task::spawn_blocking(|| {
+        let vscode_ext_glob = |marker: &str| -> bool {
+            let Some(home) = harness_home() else {
+                return false;
+            };
+            for extdir in [".vscode/extensions", ".vscode-server/extensions"] {
+                if let Ok(rd) = std::fs::read_dir(home.join(extdir)) {
+                    for e in rd.flatten() {
+                        if e.file_name().to_string_lossy().starts_with(marker) {
+                            return true;
+                        }
+                    }
+                }
+            }
+            false
+        };
+        json!({
+            "Claude Code": { "installed": find_bin("claude"), "configured": serde_json::Value::Null },
+            "Codex": { "installed": find_bin("codex"), "configured": config_mentions_cortiq(".codex/config.toml") },
+            "OpenCode": { "installed": find_bin("opencode"), "configured": config_mentions_cortiq(".config/opencode/opencode.json") },
+            "Continue": { "installed": harness_home().map(|h| h.join(".continue").is_dir()).unwrap_or(false), "configured": config_mentions_cortiq(".continue/config.yaml") },
+            "Cline": { "installed": vscode_ext_glob("saoudrizwan.claude-dev"), "configured": serde_json::Value::Null },
+        })
+    })
+    .await
+    .unwrap_or_else(|_| json!({}));
+    ok(harnesses)
+}
+
 // ───────────────────────────── protocols ───────────────────────────────────
 
 async fn get_protocols(State(state): State<SharedState>) -> ApiResult {

src/config.rs

@@ -757,7 +757,9 @@ impl Default for Config {
                 openai_completions: true,
                 openai_embeddings: true,
                 openai_models: true,
-                anthropic_messages: false,
+                // on by default: the API-keys view ships a Claude Code
+                // auto-setup snippet that targets /v1/messages
+                anthropic_messages: true,
                 mcp: false,
                 native_passthrough: true,
             },