test: export downloadFile, parsePdfFromFile, extractCwdFromJsonl

These three internal helpers are now imported by regression tests
landing in the next commits (PR #1169 follow-up). Pattern matches the
existing normalizeRemoteUrl export in gstack-global-discover.ts which
test/global-discover.test.ts already imports side-effect-free.

No change to runtime behavior; gstack has no public package entrypoint
that would re-export these, so the in-repo surface is unchanged for
callers.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

bin/gstack-global-discover.ts

@@ -273,7 +273,7 @@ function resolveClaudeCodeCwd(
   return null;
 }
 
-function extractCwdFromJsonl(filePath: string): string | null {
+export function extractCwdFromJsonl(filePath: string): string | null {
   // Read a capped prefix so huge JSONL files don't blow up memory. 64KB
   // comfortably fits the largest observed session headers; the old 8KB cap
   // would sometimes fall inside a single long line and silently drop the

browse/src/meta-commands.ts

@@ -136,7 +136,7 @@ function parsePdfArgs(args: string[]): ParsedPdfArgs {
   return result;
 }
 
-function parsePdfFromFile(payloadPath: string): ParsedPdfArgs {
+export function parsePdfFromFile(payloadPath: string): ParsedPdfArgs {
   // Parity with load-html --from-file (browse/src/write-commands.ts) and
   // the direct load-html <file> path: every caller-supplied file path
   // must pass validateReadPath so the safe-dirs policy can't be skirted

browse/src/security-classifier.ts

@@ -135,7 +135,7 @@ export function getClassifierStatus(): ClassifierStatus {
 
 // ─── Model download + staging ────────────────────────────────
 
-async function downloadFile(url: string, dest: string): Promise<void> {
+export async function downloadFile(url: string, dest: string): Promise<void> {
   const res = await fetch(url);
   if (!res.ok || !res.body) {
     throw new Error(`Failed to fetch ${url}: ${res.status} ${res.statusText}`);