fix(cloudformation): Simplified error message handling from server to client

[kddejong]

Problem

1. Duplicate error notifications: Users see the same error twice - once from the LSP client error handler and again from
   the calling code
2. Infinite retry loop: When loadStacks() fails, the loaded flag stays false, causing the UI to continuously retry loading
   stacks
3. Unclear error context: Generic error messages don't indicate which operation failed

Solution

Error handling:

• LSP client now logs errors instead of showing popups - callers handle user-facing messages
• Removed redundant error handling in refreshResourceListCommand (ResourcesManager already handles it)
• Made error messages more specific (e.g., "Loading AWS::Lambda::Function resources")

Infinite loop fix:

• Moved loaded=true to finally block in StacksManager.loadStacks() so it's set even on failure
• Applied same pattern to ResourcesManager - moved notifyAllListeners() to finally block

Tests:

• Added coverage for refreshResourceListCommand error scenarios
• Added test verifying ResourcesManager error handling

---

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[github-actions]

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[satyakigh]

We should probably get rid of the try/catch

[kddejong]

Removed

[kddejong]

unresolved. I added it back because we are expecting the error to be silently moved on from. We are already displaying the error in logs and notifications at another level so for here we just want to silently continue.