docs: answer review follow-ups on the quickstart refresh

Adds the firebase-tools floor to "Before you begin". ng add only
installs the CLI when it is absent, so a pre-existing older copy is
left in place and setup stops with the 14.0.0+ upgrade message. The
section already advised a pre-install, but a reader was told it was
optional and had no reason to expect the failure.

Marks both stale deploy pages as out of date rather than deleting
them. The deploy target wiring they describe was dropped from ng add
in 17.1.0, and their sample config omits the version option, so a
reader who wires the target by hand lands on the deprecated path and
is warned on every deploy. site/src/get-started/deploying.md is a
near-duplicate of the docs/ page, so annotating only one would leave
the other. A full rewrite of both, plus retiring docs/universal/,
is tracked separately.

Refs #3735

Author: armando-navarro

docs/deploy/getting-started.md

@@ -1,5 +1,7 @@
 # Deploy your application on Firebase Hosting & Functions
 
+> **This page is out of date.** It describes a setup flow that `ng add @angular/fire` no longer performs, and wiring the deploy target by hand from the samples below puts you on a deprecated path that warns on every deploy. For current guidance see [the Quickstart](../install-and-setup.md), step 6, and for server-side rendered apps see the [App Hosting guide](../app-hosting.md).
+
 In this guide, we'll look at how to use `@angular/fire` to automatically deploy an Angular application to Firebase hosting or functions by using the Angular CLI.
 
 `@angular/fire` uses Firebase functions to deploy your Angular universal projects, with server-side rendering enabled.

docs/install-and-setup.md

@@ -2,7 +2,7 @@
 
 ## Before you begin
 
-- **Firebase CLI.** Setup uses the Firebase CLI (`firebase-tools`). `ng add` installs it if it is missing and prompts you to sign in, so you do not have to install it yourself first. To handle it ahead of time, run `npm install -g firebase-tools` then `firebase login`.
+- **Firebase CLI.** Setup uses the Firebase CLI (`firebase-tools`), version 14 or newer. `ng add` installs it if it is missing and prompts you to sign in, so you do not have to install it yourself first. It does not upgrade a copy you already have, so an older one stops setup with `firebase-tools version 14.0.0+ is required, please upgrade and run again`. To handle it ahead of time, or to clear that error, run `npm install -g firebase-tools` then `firebase login`.
 - **On the newest Angular major, use `@next`.** If `ng add @angular/fire` reports an Angular peer-dependency conflict, your Angular version is newer than AngularFire's default (`latest`) release. Install the version-matched pre-release instead: `ng add @angular/fire@next`.
 - **Harmless CLI noise.** The Firebase CLI may print a `punycode` deprecation warning or ask about enabling extra features (for example Gemini) during setup. These come from the CLI, not from AngularFire, and are safe to ignore.
 

site/src/get-started/deploying.md

@@ -7,6 +7,8 @@ eleventyNavigation:
 
 ## Static or Server-side rendered
 
+> **This page is out of date.** It describes a setup flow that `ng add @angular/fire` no longer performs, and wiring the deploy target by hand from the samples below puts you on a deprecated path that warns on every deploy. For current guidance see [the Quickstart](https://github.com/angular/angularfire/blob/main/docs/install-and-setup.md), step 6, and for server-side rendered apps see the [App Hosting guide](https://github.com/angular/angularfire/blob/main/docs/app-hosting.md).
+
 In this guide, we'll look at how to use `@angular/fire` to automatically deploy an Angular application to Firebase Hosting or Cloud Functions by using the Angular CLI.
 
 `@angular/fire` uses Firebase functions to deploy your Angular Universal projects, with server-side rendering enabled.