feat(radar): contributor + supporter claim buttons on the activation screen (#9710)

* feat(radar): add F4/T7 contributor-claim / supporter-plans link config

Pure, DB-free src/lib/radar/links.ts resolves the two outbound "get a
supporter key" URLs (contributor GitHub-OAuth claim + supporter plans
page), same env-override pattern as RADAR_FEED_URL. No pricing/value is
ever resolved here (D14) — only the link.

* feat(radar): relay F4/T7 claim/plans links via GET /api/radar/settings

Smallest-surface option per spec: no dedicated route. The existing
settings snapshot now also returns contributorClaimUrl/supporterPlansUrl
so the dashboard client never reads process.env itself. Both are plain
public URLs, gated by the same flag/auth checks as the rest of the
response.

* feat(radar): add contributor/supporter claim buttons to activation screen

F4/T7 — "I'm a contributor" opens the GitHub OAuth claim flow;
"Support the project" opens the plans/payment page. Both links come
from the settings fetch (never a hardcoded URL in this client
component) and open in a new tab. No price/value anywhere in the
copy — the destination page is the only place pricing lives (D14).

i18n: 5 new radarPage keys (claimSectionTitle, contributorButton,
contributorHint, supporterButton, supporterHint) added to all 43
locale files with the English copy as fallback value.

* docs(radar): document F4/T7 supporter-key acquisition paths

RADAR.md: new "Getting a supporter key" section covering both claim
flows, the two env-var overrides, and the current gap (no dedicated
key-paste input in the dashboard yet — POST /api/radar/settings is the
only way to set one today). ENVIRONMENT.md + .env.example: register
RADAR_CONTRIBUTOR_CLAIM_URL / RADAR_SUPPORTER_PLANS_URL for
check:env-doc-sync.

---------

Co-authored-by: diegosouzapw <diegosouzapw@users.noreply.github.com>

docs/frameworks/RADAR.md

@@ -82,6 +82,43 @@ that lets the feed service decide which tier to serve (see
 
 ---
 
+## Getting a supporter key
+
+The activation screen (`/dashboard/radar`) links out to two flows for **obtaining** a
+supporter key. The OSS repo itself never issues one, never runs payment code, and
+**never states a price** — pricing is decided and displayed entirely on the
+destination pages, not in this repo (spec decision D14).
+
+- **"I'm a contributor"** — opens `RADAR_CONTRIBUTOR_CLAIM_URL` (default
+  `https://radar.omniroute.online/auth/github`), a GitHub OAuth claim flow hosted on
+  the private radar server. It verifies the visitor's GitHub account and grants a
+  supporter key to anyone with 5+ merged pull requests or a top-100 contributor spot
+  on the repo.
+- **"Support the project"** — opens `RADAR_SUPPORTER_PLANS_URL` (default
+  `https://radar.omniroute.online/planos`), the payment/plans page.
+
+Both URLs are resolved server-side (`src/lib/radar/links.ts`, same env-override
+pattern as `RADAR_FEED_URL`) and relayed to the dashboard through the existing
+`GET /api/radar/settings` response (`contributorClaimUrl`, `supporterPlansUrl`) — the
+client component never reads `process.env` itself.
+
+| Var                             | Purpose                                                                                      |
+| -------------------------------- | ---------------------------------------------------------------------------------------------- |
+| `RADAR_CONTRIBUTOR_CLAIM_URL`   | Overrides the contributor-claim URL (default `https://radar.omniroute.online/auth/github`).   |
+| `RADAR_SUPPORTER_PLANS_URL`     | Overrides the supporter-plans URL (default `https://radar.omniroute.online/planos`).          |
+
+Once a visitor has a key (`omr_` + 40 hex chars), it is set with `POST
+/api/radar/settings` (`{ supporterKey }`) — the same endpoint documented under
+[Data sync](#data-sync-is-a-separate-opt-in--the-privacy-promise) above.
+
+**Known gap:** the dashboard activation screen does not yet have a dedicated
+key-paste input — pasting a key today requires calling `POST /api/radar/settings`
+directly (curl, a script, or a future UI). This release only adds the two claim/plans
+buttons; the API already accepts and masks the key, but no `<input>` for it exists in
+`src/app/(dashboard)/dashboard/radar/page.tsx` yet.
+
+---
+
 ## Security model
 
 ### Ed25519 signature over exact bytes