feat: wire ai, automations, fleets and ssh-terminal to snippets (B2)

plugins/fleets/src/backend/command-variables.ts

@@ -0,0 +1,55 @@
+export interface CommandHostVars {
+  ip?: string;
+  username?: string;
+  port?: number | string;
+  name?: string;
+}
+
+const INPUT_PATTERN =
+  /\$\{INPUT_(\d+)(?::([^}$]+))?\}|\$INPUT_(\d+)(?![a-zA-Z0-9_])/g;
+
+function replaceVar(content: string, name: string, value?: string): string {
+  if (value === undefined) return content;
+  const pattern = new RegExp(`\\$\\{?${name}\\}?`, "g");
+  return content.replace(pattern, value);
+}
+
+/**
+ * $HOST/$USER/$PORT/$NAME/$INPUT_n substitution for an ad hoc fleet command,
+ * typed directly into the "run on fleet" box rather than loaded from a saved
+ * snippet. Mirrors the snippets plugin's own resolveSnippetCommand and the
+ * frontend's src/ui/lib/snippet-variables.ts - kept as a small standalone
+ * copy rather than a cross-plugin dependency for one pure function with no
+ * snippet data of its own to fetch.
+ */
+export function resolveCommandVariables(
+  content: string,
+  host: CommandHostVars | null,
+  inputValues: Record<string, string> = {},
+): string {
+  let resolved = content;
+
+  resolved = replaceVar(resolved, "HOST", host?.ip);
+  resolved = replaceVar(resolved, "USER", host?.username);
+  resolved = replaceVar(
+    resolved,
+    "PORT",
+    host?.port !== undefined ? String(host.port) : undefined,
+  );
+  resolved = replaceVar(resolved, "NAME", host?.name);
+
+  resolved = resolved.replace(
+    INPUT_PATTERN,
+    (
+      fullMatch,
+      braceDigits: string | undefined,
+      _label,
+      plainDigits: string | undefined,
+    ) => {
+      const key = `INPUT_${braceDigits ?? plainDigits}`;
+      return key in inputValues ? inputValues[key] : fullMatch;
+    },
+  );
+
+  return resolved;
+}

plugins/fleets/src/backend/routes.ts

@@ -35,7 +35,7 @@ import {
 } from "../../../../src/backend/hosts/metrics-shared/exec-elevated.js";
 import { buildPackageActionCommand } from "../../../../src/backend/hosts/metrics-shared/package-commands.js";
 import { isValidPackageName } from "../../../../src/backend/hosts/metrics-shared/validation.js";
-import { resolveSnippetCommand } from "../../../../src/backend/database/routes/snippets-execution.js";
+import { resolveCommandVariables } from "./command-variables.js";
 
 export const router = express.Router();
 
@@ -900,7 +900,7 @@ router.post(
             return { success: false, error: "Host not found" };
           }
 
-          const resolvedCommand = resolveSnippetCommand(
+          const resolvedCommand = resolveCommandVariables(
             command,
             {
               ip: fullHost.ip,