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.

web/js/i18n/de.js

@@ -602,4 +602,18 @@ export default {
   "bm.spent": "ausgegeben",
   "bm.verdict": "🏁 Fertig: Antworten {p}, ausgegeben {s}",
   "bm.clearHistory": "Alle löschen",
+
+  // harness auto-setup (API keys view)
+  "keys.h.claude": "Claude Code — ins Terminal einfügen (das Gateway spricht das Anthropic-Protokoll nativ):",
+  "keys.h.codex": "Codex — hängt den Provider an ~/.codex/config.toml an und startet:",
+  "keys.h.opencode": "OpenCode — schreibt ~/.config/opencode/opencode.json (überschreibt!) und startet:",
+  "keys.h.continue": "Continue (VS Code / JetBrains) — hängt das Modell an ~/.continue/config.yaml an:",
+  "keys.h.cline1": "Cline (VS Code) — in den Erweiterungseinstellungen wählen:",
+  "keys.h.cline2": "Einstellungen → API Provider → OpenAI Compatible, dann die Werte oben einfügen.",
+  "keys.h.note": "cortiq-auto = smartes Routing: der Router wählt das Modell pro Anfrage. Für ein festes Modell den exakten Namen angeben. Unter Windows die Skripte in Git Bash / WSL ausführen oder dieselben Variablen über die Systemumgebung setzen.",
+  "keys.h.protoOff": "Das Anthropic-Protokoll (/v1/messages) ist deaktiviert — Claude Code kann sich nicht verbinden.",
+  "keys.h.enableProto": "Aktivieren",
+  "keys.h.st.installed": "Auf der Gateway-Maschine installiert",
+  "keys.h.st.configured": "Bereits für dieses Gateway konfiguriert",
+  "keys.h.st.notFound": "Auf der Gateway-Maschine nicht gefunden",
 };