Fix TrialTimeRemaining documentation to clarify behavior for different trial types

[Copilot]

The TrialTimeRemaining property documentation was misleading and contained a fundamental conceptual error that could cause developers to implement incorrect trial logic.

The Problem

The original documentation described TrialTimeRemaining as being specifically for "usage-limited trials":

Gets the remaining time for the usage-limited trial that is associated with this app license.

However, this is contradictory because:

• Usage-limited trials expire based on usage (features used, content accessed, etc.), not time
• Time-limited trials expire based on time duration
• The ExpirationDate property explicitly documents that usage-limited trials return "December 31, 9999"

This contradiction led to confusion about when and how to use the TrialTimeRemaining property effectively.

The Solution

Updated both StoreAppLicense.TrialTimeRemaining and StoreCollectionData.TrialTimeRemaining documentation to:

1. Clarify the primary purpose: This property is intended for time-limited trials
2. Warn about usage-limited trials: Explain that the property may return misleading values for usage-limited trials since they don't expire based on time
3. Provide clear guidance: Added specific instructions for handling both trial types correctly
4. Add important warnings: Include notes about testing vs production environment differences

Key Changes

• Corrected the fundamental misunderstanding about which trial type this property serves
• Added comprehensive remarks explaining the difference between time-limited and usage-limited trials
• Provided specific implementation guidance for each trial type
• Added cross-references to related properties (IsTrial, ExpirationDate)
• Included testing environment warnings consistent with legacy API documentation patterns

This brings the documentation in line with the actual API behavior and prevents developers from implementing incorrect trial logic based on the misleading original documentation.

Fixes #1764.

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