feat: add community event submissions

[Elvis020]

Summary

Adds a simple public event submission flow to DevCongress and sends proposals to Events Management for organizer review.

What changed

• Adds a three-step event form with inline validation, custom date/time zone/type controls, draft recovery, navigation warnings, and Turnstile.
• Consolidates public discovery under Events and adds the create-event entry points.
• Loads published events from the generic EMS events feed, with the existing meetup content as a build fallback.
• Preserves the permanent community-first Support Us and Join Slack navbar actions; no event-submission CTA is added during beta.
• Adds one fail-closed build-time switch for the direct-link beta form.
• Keeps the static site refreshed through pushes, manual runs, and the daily 06:17 UTC build.

Submission lifecycle

1. A visitor completes the form and passes Turnstile.
2. The website sends the proposal to the EMS public submissions endpoint.
3. EMS validates the request, applies rate limits, saves it as pending, and queues a receipt email.
4. An organizer reviews it in the EMS submissions queue.

Approval

• EMS idempotently promotes the proposal to a published community event.
• An approval email is queued for the submitter.
• It becomes available through the public events API and appears on the static website after its next build.

Rejection

• The organizer selects a reason and can add a submitter-facing message plus a private internal note.
• EMS records the rejection and queues the rejection email.
• No public event is created.

Email delivery is handled through the EMS outbox, so failed sends can be retried without repeating the moderation action.

Minimal launch plan

The launch control is a GitHub Actions repository variable consumed by both static deployment workflows:

Stage	PUBLIC_EVENT_SUBMISSIONS_ENABLED	Result
Disabled/default	false or unset	/events/submit/ redirects to /events/.
Private beta	true	The direct form URL works and remains noindex; the website renders no submission CTA.

For beta, share the direct URL with selected testers and monitor successful/failed submissions, Turnstile and rate-limit errors, moderation workload, and receipt/approval/rejection emails. To stop website submissions, set the variable to false and rerun both production workflows. The permanent public entry point will be chosen after beta.

Architecture note

The EMS origin is intentionally hard-coded as https://em.devcongress.org for now. It is a public origin, not a secret.

Removing it from source would require additional setup: build-time repository variables for Astro, a runtime variable plus a Worker entrypoint/proxy because the current Worker is static-assets-only, and corresponding local configuration. Reviewer input is requested before introducing that deployment architecture.

Screenshots

1. Event details

2. Place and time

3. Contact and human check

4. Submitted for review

Verification

• pnpm exec tsc --noEmit
• Enabled beta build with no submission CTA and an active noindex form
• Disabled build with the submission route redirected to Events
• pnpm deploy:dry-run
• Manual submission through the deployed EMS endpoint and Turnstile to the success state

[bubunyo]

We should not remove the 2 current main items. Remember we are a community first.

Also, this should not be the way we launch this. Lets come up with a minimal launch plan at least. we can gate this button and release this for some public beta.

[Elvis020]

ok, i will bring it back, removed it because i thought it looked redundant since it's already in the hero section...

I have added a Minimal launch plan in the description as well