docs: cover the options and functions the JS API reference was missing

[floyd-soomgo]

Background

docs/api-js.md is the JS API reference. It came from upstream Microsoft CodePush and never caught up with what this fork added, so it documented 8 of CodePushOptions' 17 options.

The most consequential omission: releaseHistoryFetcher is required — an app cannot be configured without it — and the reference did not mention it exists. Six callbacks this fork added were described in the README's "4-1. Telemetry Callbacks" section but nowhere in the reference. And clearUpdates was the only one of the namespace's eight functions with no section at all, which is why the entry at the top of the file linked to an anchor that resolved to nothing.

None of this is new drift. It is what the reference has looked like since the fork started adding options.

Changes

CodePushOptions — nine entries added. releaseHistoryFetcher (required, with what it receives and must return), updateChecker (deprecated, what replaces it, and that setting it takes releaseHistoryFetcher out of the path entirely), ignoreFailedUpdates (typed never here, so accepted only by sync() — the restriction is documented rather than glossed), and the six callbacks onUpdateSuccess, onUpdateRollback, onDownloadStart, onDownloadSuccess, onSyncError, onRolloutSkipped.

SyncOptions — two entries added. ignoreFailedUpdates, documented in full here since this is where it is actually usable, and rollbackRetryOptions. The section's intro claimed the two option sets differ only in checkFrequency; that stops being true once ignoreFailedUpdates is listed, so it now names both exceptions.

codePush.clearUpdates — new section, and the link at the top of the file now points at an anchor that exists. The link's target changed from #clearupdates to #codepushclearupdates, matching the eight sibling entries; a bare #### clearUpdates heading would have resolved the old anchor but broken the naming every other function section follows.

onUpdateArchiveResult was restructured while adjacent entries were being written — it had grown into one run-on entry carrying call timing, the result's composition, fallback semantics, the observation-only guarantee and the type link.

Existing entries were not reordered. rollbackRetryOptions still sits out of alphabetical order after updateDialog's sub-list, where it already was.

Verification

Nothing checks this file automatically, which is why it drifted. The check is a survey that pulls the option names out of the typings and subtracts the ones the reference lists:

T=typings/react-native-code-push.d.ts
{ awk '/^export interface CodePushOptions/,/^}/' $T; awk '/^export interface SyncOptions/,/^}/' $T; } \
  | grep -oE '^    [a-zA-Z]+\??:' | tr -d ' ?:' | sort -u > /tmp/all.txt
awk '/^##### CodePushOptions/{c=1} c&&/^##### /&&!/CodePushOptions/{exit} c' docs/api-js.md \
  | grep -oE '^\* __[a-zA-Z]+__' | sed 's/\* __//; s/__//' | sort > /tmp/doc.txt
comm -23 /tmp/all.txt /tmp/doc.txt

Empty for both sections after these commits. Every in-page anchor was also checked against the real headings: 19 unique targets, 26 headings, none unresolved.

npm run jest 259/259 and type:cli / type:scripts / type:e2e all green — formality for a markdown change, but run. Only docs/api-js.md changed.

Note that npm run typecheck does not pass on this stack: type:src fails at src/specs/NativeCodePush.ts:4 with TS2305 on EventEmitter, which predates all of this work.

Follow-ups

• onRolloutSkipped's type is wrong. typings/react-native-code-push.d.ts:234 declares (label: string, error: Error) => void, but src/CodePush.js:86 calls onRolloutSkipped?.(latestVersion) — one argument, and there is no error on that path at all; the release was passed over by a rollout bucket check, not by a failure. A TypeScript app reading error.message compiles and then crashes. The reference documents the runtime signature and flags the mismatch inline; fixing the type is a production change and did not belong here.
• The survey above should be a script. Wiring it into npm run would catch the next option added without a reference entry, which is the only reason this gap grew as large as it did.