chore: Clarify project scope and development priorities (#2149)

Expand scope to support multiple e-ink devices beyond X4. Add guiding
principle to fill gaps in stock firmware rather than duplicate
functionality. Establish current focus on memory/flash optimization and
code cleanup. Temporarily freeze new themes and network connectors to
consolidate codebase before multi-device expansion.

.github/PULL_REQUEST_TEMPLATE.md

@@ -3,16 +3,34 @@
 * **What is the goal of this PR?** (e.g., Implements the new feature for file uploading.)
 * **What changes are included?**
 
+## Scope Check
+
+CrossPoint is intentionally narrow. See [SCOPE.md](../blob/master/SCOPE.md) and [ROADMAP.md](../blob/master/ROADMAP.md).
+Please confirm:
+
+- [ ] I have read SCOPE.md and ROADMAP.md.
+- [ ] This PR is **not** a new built-in theme (themes are temporarily closed pending the move to SD-loaded themes).
+- [ ] This PR is **not** a new external network connector (sync engine, cloud storage, remote file access, etc.).
+- [ ] This PR is **not** an interactive app, writing tool, RSS/news/browser, media playback, or PDF feature.
+- [ ] The stock firmware does not already handle this well, **and** no other popular CrossPoint fork already does
+      (or, if one does, I explain why CrossPoint still needs it below).
+- [ ] If this PR touches `freeink-sdk/`, `lib/hal/`, the bootloader, OTA, or recovery code, I have coordinated with
+      the relevant maintainer.
+
+**If this PR was opened against the previous (broader) scope and was already in flight under Phase 0, link the
+relevant Discussion or issue so reviewers can see the history.**
+
 ## Additional Context
 
-* Add any other information that might be helpful for the reviewer (e.g., performance implications, potential risks, 
+* Add any other information that might be helpful for the reviewer (e.g., performance implications, potential risks,
   specific areas to focus on).
+* Memory / flash impact, if known.
 
 ---
 
 ### AI Usage
 
-While CrossPoint doesn't have restrictions on AI tools in contributing, please be transparent about their usage as it 
+While CrossPoint doesn't have restrictions on AI tools in contributing, please be transparent about their usage as it
 helps set the right context for reviewers.
 
 Did you use AI tools to help write this code? _**< YES | PARTIALLY | NO >**_