Dashboard data store - Warn when the context store can't hold a live proxy [2/3]

[n-lark]

Description

The global.dashboardStore store is a Proxy, which is behavior rather than data, so it quietly stops working in two situations. This layer catches both and warns instead of failing silently.

1️⃣ Cache-off context store

A persistent context store with cache: false keeps no in-memory copy, so every read hands back plain data with the proxy stripped. isInMemoryBacked() probes for this up front, and ui-base injects the store only when it is safe, otherwise it warns.

2️⃣ Replacement

global.set('dashboardStore', <anything>) discards every widget's stored value. attachToContext remembers the store it injected, per context, so it catches any replacement, including undefined and primitives, which a shape check misses. Then re-creates the store, rehydrates any plain data, and calls onReplaced. A restart rehydrating plain data is not a replacement, so it stays quiet.

Related Issue(s)

Relates to #2236

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production
• Link to Changelog Entry PR, or note why one is not needed.

Labels

• Includes a DB migration? -> add the area:migration label