[theycallmeswift]

Two BirdsBirdBirds tests fail on macOS, and this makes them pass without changing the package. The 413 test now sends only the headers, because the server refuses from Content-Length and a client still writing the body can get EPIPE first. Watcher tests now repeat their first save until it is reported, because fs.watch on macOS can miss a change made just after it starts. Closes #20.

Decide

Nothing. Whether the server should let a client read its 413 before dropping the connection is in #22.

Ready gate

Step	Evidence
Tests and lint	npm run verify: ok for all three packages. npm run lint: 0 issues in 15 files. BirdsBirdBirds tests: 91 of 91 in five runs in a row. Full npm test on macOS: 191 of 192; the failure is covered under Skipped tests.	✅
Red run	On main, the 413 test fails on every macOS run with write EPIPE. Watcher tests on main under background file churn failed in three of eight runs, in three different tests. On this branch, five runs under the same churn pass 8 of 8 each.	✅
Sibling sweep	Searched for watcher tests that wait on the first save after startWatching. The appears-once, redrawn, burst, and page-server tests now use saveUntilReported. The complete-PNG test writes its PNG after two quiet waits, and the negative tests can't fail from a missed event, so they are unchanged.	✅
Docs and specs	None: tests only.	✅
Standalone run	No package changed.	✅
Editorial pass	Reread against docs/style/; the two new helpers each document why they exist.	✅
Skipped tests	None skipped. On macOS the Mad Libs install test fails with "Missing: package@ from lock file" because the OS temp directory is under the /var symlink. #19 fixes that. CI runs on Linux.	✅
Secrets, permissions	Not touched.	✅

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