[armando-navarro]

Checklist

• Issue number for this PR: collection() missing type arguments #3081 (and its duplicate collection function has no generic type #3073)
• Docs included?: yes, this is a docs-only change.
• Test units included?: no, Markdown only.
• Breaking change?: no.
• In a clean directory, yarn install, yarn test run successfully? Not run, the change is four Markdown files. npm run lint passed on the commit.

Description

The README, the quickstart (docs/install-and-setup.md) and the v7 upgrade guide show collectionData<Item>(collection(firestore, 'items')), which doesn't compile.

collection() returns a reference typed DocumentData, and collectionData<Item> asks for Query<Item>, so TypeScript reports TS2345.

docs/firestore.md casts instead, collectionData(ref) as Observable<UserProfile[]>, which compiles but checks nothing about the stored documents. #3081 and #3073 are readers asking for a typed collection<T>(), and the thread workarounds are the cast and a helper service.

The signature comes from the Firebase SDK, where the type lives on the reference through withConverter() (see #2931). The docs now teach that.

Changes

• README.md and docs/install-and-setup.md: the Item example attaches a FirestoreDataConverter<Item> whose fromFirestore substitutes '' for a missing or non-string name, reads through collection(...).withConverter(itemConverter), and calls collectionData() with no type argument. One sentence under the example links to the new section.

• docs/firestore.md: the UserProfile example gets the same converter, the cast goes, and a new "Typed reads" subsection explains why the two shortcuts do not give a typed read, where the default-versus-throw choice lives (fromFirestore runs on every document, so a throw there errors the observable at the first bad document), and that idField performs no validation.

• docs/version-7-upgrade.md: a sentence above the v6-to-v7 table defines docRef as a converter-typed reference, the collection<T>(docRef, 'bar') // CollectionReference<T> row is corrected (both collection(reference, path) overloads return CollectionReference<DocumentData>), docData's return type gains | undefined, and the code-splitting snippet uses a converter and imports concatMap.

Checked on a fresh Angular 22.2.4 app with @angular/fire 22.0.0-rc.0: the quickstart text builds as written, the previous collectionData<Item>(aCollection) line fails the same build with TS2345, and against the Firestore emulator the documented converter keeps emitting on malformed documents while a throwing one ends the subscription.

Not changed: site/src/get-started/quick-start.md still shows the cast. site/ is the unbuilt duplicate docs tree whose fate is a separate decision.

Fixes #3081
Fixes #3073