promote: develop caveat in the PR template (develop -> main)

[LukasWodka]

Promotes #113 — the note that closing keywords do not fire on a develop merge.

Ordering matters here: backend#1373 deletes the per-repo PR templates so repos inherit this one, and repos inherit the copy on main. Both template improvements (#111 expand-then-contract, #113 the develop caveat) need to be on main before those deletions land, or the nine repos would inherit a template missing exactly the two things their own templates knew.

Docs-only, already reviewed and Bugbot-clean on #113.

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Note

Low Risk
Comment-only change to the PR template with no runtime or security impact.

Overview
Updates the Related section guidance in the org-wide .github/pull_request_template.md so authors know that closing keywords do not auto-close issues when PRs merge into develop instead of the default branch—they should confirm the linked issue actually closed.

Docs-only promotion of the same note from #113, timed so main has this text before per-repo templates are removed and repos inherit this file.

^{Reviewed by Cursor Bugbot for commit 480a8f4. Bugbot is set up for automated code reviews on this repo. Configure here.}

[LukasWodka]

👋 Heads-up — Code review queue is at 41 / 30

Above the WIP limit. The team convention is to review existing PRs before opening new work.

Open PRs currently in Code review (oldest first):

• averaging-service#255 — chore(ci): enable Dependabot security updates · author: @LukasWodka · no reviewer assigned
• backend#1146 — docs(rfc): platform cost & autoscaling architecture · author: @saadqbal · reviewer: @LukasWodka, @saqlainsyed007, @aptracebloc
• backend#1201 — docs(rfc): Data spaces & federated dataset composition (draft) · author: @LukasWodka · reviewer: @saadqbal
• backend#1217 — docs(rfc): Dataset integrity & score reproducibility (draft) · author: @LukasWodka · reviewer: @saadqbal
• backend#1261 — RFC-BACKEND-0008: board & process reset (decision RFC — for markup) · author: @LukasWodka · reviewer: @saadqbal
• backend#1284 — docs(deploy): backend deploy runbook skeleton (#1263) · author: @LukasWodka · no reviewer assigned
• backend#1332 — feat(check-model): allow KNN/GaussianProcess on a single-edge owned dataset (#923 follow-up) · author: @divyasinghds · no reviewer assigned
• backend#1353 — chore(ci): baseline historical gitleaks findings + wire caller · author: @LukasWodka · no reviewer assigned
• backend#1361 — feat(tasks): bound ExperimentQueue growth for PAUSED experiments (backend#1351) · author: @saqlainsyed007 · reviewer: @aptracebloc
• claude-skills#14 — feat(skill): add tracebloc-frontend-app skill · author: @waqaskhanroghani · reviewer: @saadqbal

Pull from review before opening new work. (This is a nudge from the kanban WIP check, not a block.)