Refactor FXIOS-15349 [Technical Debt] [Redux] Use @Copyable macro for TabPeekState

[hkarmoush]

📜 Tickets

Jira ticket
Github issue

💡 Description

Migrates TabPeekState (Redux state) to use the @Copyable macro from the ModifiedCopy package, replacing the reducer's manual full-struct reconstruction with chained .copy(property:) calls. This follows the same pattern already used by other Redux states in the codebase (e.g. SearchBarState, HomepageState).

Pure technical-debt refactor — no behavior change, no public API change. showCloseTab is intentionally left out of the .copy() chain since the existing reducer never updates it (always stays at its default true); confirmed via TabPeekState( grep that no call site ever constructs it with a non-default value, so this is behavior-identical to before.

TabPeekStateTests.swift is unmodified.

🎥 Demos

N/A — no UI or behavior change.

📝 Checklist

• I filled in the ticket numbers and a description of my work
• I updated the PR name to follow our PR naming guidelines
• I ensured unit tests pass and wrote tests for new code — note: could not run xcodebuild test locally (no iOS Simulator runtimes installed in this environment); relying on CI to verify TabPeekStateTests (5 existing tests) still pass unmodified
• N/A — no UI changes
• N/A — no telemetry changes
• N/A — no string changes
• N/A — no documentation changes needed

[PARAIPAN9]

Thanks @hkarmoush for your contribution. There is one important change to make in order for the project to build.

[PARAIPAN9]

From the build errors I believe we need to add let windowUUID: WindowUUID above let showAddToBookmarks: Bool.

[PARAIPAN9]

Shouldn't we use here: defaultState(from state:_ )? CC: @ih-codes.

[ih-codes]

Yes, good catch @PARAIPAN9, it should. 👀 Also on the two guard return lines above. But that can be in a separate PR, since it's not related to adding @Copyable. So I don't think @hkarmoush needs to worry about that here.

[PARAIPAN9]

@hkarmoush , everything's ok, we just need to address this to make sure the project builds without errors: #34744 (comment)