chore: update docs for cli and self-hosted (#9991)

* chore: update links in self hosted docs

* chore: add npm to cli installation guide

apps/reference/docs/guides/cli.mdx

@@ -22,6 +22,16 @@ You can also use the CLI to manage your Supabase projects, handle database migra
     {label: 'Windows', value: 'windows'},
     {label: 'Linux', value: 'linux'},
   ]}>
+<TabItem value="npm">
+
+Install the CLI as dev dependency via [npm](https://www.npmjs.com/package/supabase):
+
+```sh
+npm install supabase --save-dev
+```
+
+</TabItem>
+
 <TabItem value="macos">
 
 Install the CLI with [Homebrew](https://brew.sh):
@@ -78,6 +88,14 @@ When a new [version](https://github.com/supabase/cli/releases) is released, you
     {label: 'Windows', value: 'windows'},
     {label: 'Linux', value: 'linux'},
   ]}>
+<TabItem value="npm">
+
+```sh
+npm update supabase --save-dev
+```
+
+</TabItem>
+
 <TabItem value="macos">
 
 ```sh

apps/reference/docs/guides/hosting/overview.mdx

@@ -49,7 +49,8 @@ The "middleware" is everything except Postgres, and it should work with any Post
 ### Extensions
 
 Supabase requires some Postgres extensions to be enabled by default for the API and Auth system to work. You can find the extensions inside the
-[schema initialization script](https://github.com/supabase/supabase/blob/master/docker/volumes/db/init/00-initial-schema.sql).
+[schema migration scripts](https://github.com/supabase/postgres/tree/develop/migrations). These are mounted at `/docker-entrypoint-initdb.d`
+to run automatically when starting the database container.
 
 We recommend installing all extensions into an `extensions` schema. This will keep your API clean,
 since all tables in the `public` schema are exposed via the API.
@@ -72,7 +73,8 @@ For working with JWT and Auth functions.
 ### Roles
 
 Supabase creates several default roles in your Postgres database. To restore defaults at any time you can run the commands inside the
-[schema initialization script](https://github.com/supabase/supabase/blob/master/docker/volumes/db/init/00-initial-schema.sql).
+[schema initialization scripts](https://github.com/supabase/postgres/tree/develop/migrations/db/init-scripts). Remember to change your
+[role passwords](./docker#securing-your-setup) before deploying to production environments.
 
 ##### `postgres`