Rebuild: phase 1 modules from the current app, ordered by pipeline stage

lib/nntp (XOVER client, Xref, GROUP), lib/headers (subjects, file keys,
segments from overview lines; the yEnc path stays behind for phase 2),
lib/release (identity, random names, now in lib), lib/files (aggregator,
volume names), lib/rules (posting tools, owner by priority, release
verdicts), lib/chunks (release chunk codec). Their unit tests came along;
new ones for codec, rules and volumes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lib/nntp/group.ts

@@ -0,0 +1,23 @@
+export interface GroupInfo {
+  count: bigint
+  first: bigint
+  last: bigint
+  name: string
+}
+
+/**
+ * Parses a `211 count first last name` GROUP reply (RFC 3977 §6.1.1).
+ *
+ * nntp-js's own `group()` destructures this reply without skipping the status
+ * code, so its `first`/`last` are off by one field. Pass it `result.resp`.
+ */
+export function parseGroupResponse(resp: string): GroupInfo {
+  const match = /^211\s+(\d+)\s+(\d+)\s+(\d+)\s+(\S+)/.exec(resp.trim())
+  if (!match) throw new Error(`Unexpected GROUP response: ${resp}`)
+  return {
+    count: BigInt(match[1]),
+    first: BigInt(match[2]),
+    last: BigInt(match[3]),
+    name: match[4],
+  }
+}