[MBL-1814] PLOT plan selector component

[jovaniks]

📲 What

Create a new Payment Plan Selector component to allow users to select a payment plan option. The component will feature the options:

Pledge in full (default selection)
Pledge over time (just contains the initial state, it will be extended in MBL-1815)

🤔 Why

This feature is part of the Pledge Over Time (PLOT) initiative. It provides backers with more flexibility in how they contribute to projects. By implementing this, backers can choose whether to pay upfront or in multiple payments.

🛠 How

• UI: A new Payment Plan Selector component will be implemented in the new Checkout UI.
• State Machine: The component will have three primary states:
  • Default: Pledge in full (selected by default).
  • PLOT Selected: Pledge over time, when eligible (displays incremental charges).
  • PLOT Ineligible: Disabled when PLOT conditions are not met (e.g., pledge amount over $150 or ineligible).
• Feature Flags:
  • API: The project.isPledgeOverTimeAllowed flag from the API will determine whether the Pledge over time option is available for the project.
  • App: The feature flag pledge_over_time will control the availability of this option at both the project level and for individual backers.

👀 See

• Jira
• Spike
• Figma

Plot Allowed	Plot Not Allowed

✅ Acceptance criteria

• The component is displayed when bot feature flags are ON.

[scottkicks]

Looking pretty good!

I added some Prelude and naming cleanup opportunities and also a question about whether we need to use a UITableView for this. I think we might be able to avoid some overhead from creating a new data source and table view cells by using a more basic UIStackView + UIView approach. You might have looked into this as an alternative already so lmk if you prefer the table view approach here.

I also think we might able to reduce some code by making a shared UIView for each payment plan option. They both have a selectable button and label that can be shared. Then we could dynamically show the PLOT details as needed. What do you think?

We should also probably add unit test coverage to PledgePaymentPlansViewModel if possible.

[nativeksr]

	1 Warning
⚠️	Big PR

Generated by 🚫 Danger

[scottkicks]

Thanks for making those changes!

Just want to make sure that the "eligible but pledge amount is < $150" state is accounted for as well before merging. I don't see it in the gifs you added in the PR description

[jovaniks]

Thanks for making those changes!

Just want to make sure that the "eligible but pledge amount is < $150" state is accounted for as well before merging. I don't see it in the gifs you added in the PR description

The plan is to tackle this validation in the ticket https://kickstarter.atlassian.net/browse/MBL-1816