app-backend: changeset and API report for asset cache and header updates

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/wild-pugs-call.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-app-backend': patch
+---
+
+Updated the cache control headers for static assets to instruct clients to cache them for 14 days.

.changeset/witty-avocados-bow.md

@@ -0,0 +1,7 @@
+---
+'@backstage/plugin-app-backend': patch
+---
+
+Added a new asset cache that stores static assets from previous deployments in the database. This fixes an issue where users have old browser tabs open and try to lazy-load static assets that no longer exist in the latest version.
+
+The asset cache is enabled by passing the `database` option to `createRouter`.

plugins/app-backend/api-report.md

@@ -6,6 +6,7 @@
 import { Config } from '@backstage/config';
 import express from 'express';
 import { Logger as Logger_2 } from 'winston';
+import { PluginDatabaseManager } from '@backstage/backend-common';
 
 // Warning: (ae-missing-release-tag) "createRouter" is exported by the package, but it is missing a release tag (@alpha, @beta, @public, or @internal)
 //
@@ -19,6 +20,7 @@ export interface RouterOptions {
   appPackageName: string;
   // (undocumented)
   config: Config;
+  database?: PluginDatabaseManager;
   disableConfigInjection?: boolean;
   // (undocumented)
   logger: Logger_2;