docs: clarify pull request motivation

.github/pull_request_template.md

@@ -5,7 +5,7 @@ Describe the problem and fix in 2–5 bullets:
 If this PR fixes a plugin beta-release blocker, title it `fix(<plugin-id>): beta blocker - <summary>` and link the matching `Beta blocker: <plugin-name> - <summary>` issue labeled `beta-blocker`. Contributors cannot label PRs, so the title is the PR-side signal for maintainers and automation.
 
 - Problem:
-- Why it matters:
+- Solution:
 - What changed:
 - What did NOT change (scope boundary):
 
@@ -35,6 +35,12 @@ If this PR fixes a plugin beta-release blocker, title it `fix(<plugin-id>): beta
 - Related #
 - [ ] This PR fixes a bug or regression
 
+## Motivation
+
+Explain why this change should exist now. Link it to the user pain, failure mode, maintainer need, or product goal. If this is purely mechanical, write `N/A`.
+
+-
+
 ## Real behavior proof (required for external PRs)
 
 External contributors must show after-fix evidence from a real OpenClaw setup. Unit tests, mocks, lint, typechecks, snapshots, and CI are supplemental only. Screenshots are encouraged even for CLI, console, text, or log changes; terminal screenshots and copied live output count. Be mindful of private information like IP addresses, API keys, phone numbers, non-public endpoints, or other private details when providing evidence.