fix: resolve 422 from Replicate + add local Cog Docker mode

- replicate-translate: parse owner/model:hash correctly — extract only
  the hash portion for the version field, and use the model endpoint
  (POST /v1/models/{owner}/{model}/predictions) which avoids 422
  'Invalid version' errors when sending the full owner/model:hash string.

- Add local Cog mode: when replicateMode="local", calls the local Docker
  container directly (no Replicate API key needed), default endpoint
  http://localhost:5030/predictions (host port 5030 → container port 5000).

- settings-store: add replicateMode ("cloud"|"local") and localEndpoint
  fields with env var fallbacks REPLICATE_MODE and LOCAL_MODEL_ENDPOINT.

- admin panel: Radio selector for Cloud vs Local mode; shows docker run
  command snippet and local endpoint URL field when local is selected;
  hides Replicate API token field in local mode (not needed).

Local model startup:
  docker run -d -p 5030:5000 \
    r8.im/jigsawstack/text-translate@sha256:454df4c...

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

utils/settings-store.ts

@@ -1,11 +1,15 @@
 import fs from "fs";
 import path from "path";
 
+export type ReplicateMode = "cloud" | "local";
+
 export type Settings = {
     replicateApiToken: string;
     jigsawApiKey: string;
     modelVersion: string;
     replicateEnabled: boolean;
+    replicateMode: ReplicateMode;
+    localEndpoint: string;
     adminPasswordHash: string;
 };
 
@@ -14,6 +18,8 @@ const DEFAULT_SETTINGS: Settings = {
     jigsawApiKey: process.env["JIGSAWSTACK_API_KEY"] ?? "",
     modelVersion: "jigsawstack/text-translate:454df4c49941c05dea05175bd37686d0872c73c1f9366d1c2505db32ade52a89",
     replicateEnabled: false,
+    replicateMode: (process.env["REPLICATE_MODE"] as ReplicateMode) ?? "cloud",
+    localEndpoint: process.env["LOCAL_MODEL_ENDPOINT"] ?? "http://localhost:5030/predictions",
     adminPasswordHash: process.env["ADMIN_PASSWORD"] ?? "admin"
 };