Update programme timeline on website

[khairahscorner]

We need to update the current website with the new timelines for 2026

Long-term: https://www.womencodingcommunity.com/mentorship-long-term-timeline
Ad-hoc:

1. Long-term period: April to September 2026, registration in March

• Launch event tentative for IWD week (in-person); for now, keep date neutral and update to March (IWD week in March)
• add extra card about 2026 long-term slated for 6 months, the team will provide full support for long-term during this timeline but mentors / mentees can continue the relationship until the final month of the full programme - November)
• Check-ins events: undecided(?), we will monitor relationships more closely each month

2. Ad-hoc: May to November 2026

We also need to update the overview page with 2026 coming soon banner

• Reference this past banner and modify accordingly

We also need to ensure these updates are reflected in the fallback data on the platform backend repo for the upcoming platform

• reference: https://github.com/Women-Coding-Community/wcc-backend/blob/main/src/main/resources/init-data/adHocTimelinePage.json