Resolve database pending_updates duplicates bug; refactor database schema & model sharing

[lgarber-akamai]

📝 Description

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✔️ How to Test

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[Copilot]

Pull Request Overview

This PR resolves a bug where duplicate entries appeared in the pending_updates field of managed database resources and refactors the database-related code by centralizing shared functionality into a new databaseshared package.

• Implements deduplication logic for pending updates using a new FrameworkDropDuplicatesIter helper function
• Extracts common database models, schema attributes, and utility functions into a shared linode/helper/databaseshared package
• Adds comprehensive test coverage with HTTP client modification support to verify the deduplication fix

Reviewed Changes

Copilot reviewed 47 out of 47 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
linode/helper/http.go	Adds HTTPClientModifier type definition for modifying HTTP clients
linode/helper/framework_util.go	Adds FrameworkDropDuplicatesIter function for deduplicating iterator values
linode/helper/databaseshared/*.go	New package containing shared database models, schemas, and utilities extracted from individual database modules
linode/helper/database.go	Removed (functionality moved to databaseshared package)
linode/framework_provider_config.go	Adds support for applying HTTP client modifiers during client initialization
linode/databases/*.go	Updates to use shared database models from databaseshared package
linode/database*/*.go	Refactored to use shared functionality from databaseshared package instead of duplicated code
linode/acceptance/*.go	Adds test infrastructure for HTTP response overrides and database-specific test helpers

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[Copilot]

The day_of_week attribute is defined as StringAttribute in the resource schema (line 42) but the model field DayOfWeek is types.Int64 (line 24). This type mismatch will cause runtime errors when converting between schema and model.

Suggested change

	"day_of_week": resourceSchema.StringAttribute{
	Description: "The numeric reference for the day of the week to perform maintenance.",
	Optional: true,
	Computed: true,
	Validators: []validator.String{
	stringvalidator.OneOf(slices.Collect(maps.Keys(dayOfWeekStrToKey))...),
	"day_of_week": resourceSchema.Int64Attribute{
	Description: "The numeric reference for the day of the week to perform maintenance.",
	Optional: true,
	Computed: true,
	Validators: []validator.Int64{
	int64validator.OneOf(slices.Collect(maps.Values(dayOfWeekStrToKey))...),

[Copilot]

The description for hour_of_day is incorrect. It describes maintenance frequency instead of the hour of day when maintenance should occur. This should describe the hour value (0-23) when maintenance is scheduled.

Suggested change

	Description: "How frequently maintenance occurs. Currently can only be weekly.",
	Description: "The hour of the day (0-23) when maintenance is scheduled to occur.",

[Copilot]

Variable ObjectTypePrivateNetwork incorrectly references ResourceAttributeUpdates instead of PrivateNetworkResourceAttribute. This will cause a type mismatch when flattening private network data.

Suggested change

	var ObjectTypePrivateNetwork = ResourceAttributeUpdates.GetType().(types.ObjectType)
	var ObjectTypePrivateNetwork = PrivateNetworkResourceAttribute.GetType().(types.ObjectType)

[Copilot]

Using PrivateNetworkDataSourceAttribute for a resource schema is incorrect. Should use PrivateNetworkResourceAttribute instead, as this is a resource, not a data source.

Suggested change

	"private_network": databaseshared.PrivateNetworkDataSourceAttribute,
	"private_network": databaseshared.PrivateNetworkResourceAttribute,