Claude Opus 5.5 (effort default (no --effort flag) · thinking on) on Model ladder: fix 10 real merged bugs with tests hidden

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  "result": "Fixed: a fractional size now acts like its integer part in both the node and browser builds, for both `customAlphabet()` and `customRandom()`. `customAlphabet('0123456789abcdef')(16.5)` now returns 16 random characters, such as `26ec0dbdd7efae32`.\n\n**Cause:** the functions returned by `customRandom()` used `size` directly as a loop counter. With 16.5, the counter took values like 15.5, 14.5\u2026, so `bytes[15.5]` was `undefined`. `undefined & mask` is `0`, which gave the first alphabet character every time. Also, `id.length >= 16.5` only stopped at 17 characters. The node build's `customAlphabet()` fast path already did `size |= 0`. But node's `customRandom()` didn't, and the browser's `customAlphabet()` goes through `customRandom()`.\n\n**Fix:**\n- **`index.js` and `index.browser.js`:** both functions returned by `customRandom()` now start with `size |= 0`. That's the same idiom the codebase already uses in `random()` and in node's `customAlphabet()`.\n- **`index.browser.js`:** I removed the `size | 0` that `customAlphabet` applied to its default size. `customRandom()` now truncates every size, so it did nothing, and dropping it offsets the bytes I added to the browser bundle.\n\n**Tests:** I added \"truncates fractional size\" tests in `test/index.test.js` for `customAlphabet` (power-of-two and other alphabets) and for `customRandom`. Both run against the node and browser builds. They fail without the fix and pass with it, and the full suite passes (87/87 with `bnt`).\n\nI couldn't run `size-limit` or `oxlint`: this sandbox has Node 20, and both tools fail to start under it. The browser `customAlphabet` bundle (limit 219 B) changes by a few bytes, so run `pnpm test` on a supported Node version (22 or later) to confirm the size check and lint still pass.",
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