Nucleic: Gitea Runner macOS VM Support

Sources/RunnerCore/RunnerNaming.swift

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+import Foundation
+
+/// Naming scheme for the ephemeral runners this host registers with Gitea.
+///
+/// Every booted VM registers under a **globally unique** name. That uniqueness
+/// is what makes the reconcile loop safe: when a VM dies uncleanly, Gitea keeps
+/// the runner row forever (rows are only swept at midnight, and never at all if
+/// the runner never claimed a task), so we must be able to look at a runner row
+/// and decide "this name is mine and no live VM of mine owns it" without any
+/// ambiguity. A shared or reused name would make that decision impossible.
+public enum RunnerNaming {
+    /// Generates a fresh runner name.
+    ///
+    /// - Parameter prefix: The configured prefix, e.g. `macos-vm-`.
+    /// - Returns: `prefix` followed by a lowercase UUID, e.g.
+    ///   `macos-vm-3f1c2f8e-...`.
+    public static func makeRunnerName(prefix: String) -> String {
+        prefix + UUID().uuidString.lowercased()
+    }
+
+    /// Whether a runner name reported by Gitea was minted by this host.
+    ///
+    /// - Parameters:
+    ///   - name: A runner name from `GET /api/v1/admin/actions/runners`.
+    ///   - prefix: The configured prefix.
+    /// - Returns: `true` when the reconcile loop may consider deleting it.
+    public static func hasPrefix(_ name: String, prefix: String) -> Bool {
+        // An empty prefix would match every runner on the instance, including
+        // other people's. The reconcile loop deletes what this returns true for,
+        // so refuse rather than match everything. `validated()` also rejects an
+        // empty `namePrefix`; this is the second line of defence.
+        guard !prefix.isEmpty else { return false }
+        return name.hasPrefix(prefix)
+    }
+}