docs: remove third-party plugin name from design doc

Specification-first wording: features are specified from user behavior,
not benchmarked against a named product.

docs/plans/2026-09-13-wprecache-design.md

@@ -2,20 +2,20 @@
 
 ## Overview
 
-Create a commercial-grade WordPress performance plugin with feature parity to WP Rocket, implemented via clean-room methodology. The plugin will be open source (GPL-2.0+) and provide page caching, file optimization, and image optimization.
+Create a commercial-grade, open source (GPL-2.0+) WordPress performance plugin providing page caching, file optimization, and image optimization. Features are written from specification, never derived from any existing plugin's source code.
 
-## Clean-Room Methodology
+## Specification-First Methodology
 
 ### Rules
 
-1. **No code reuse.** Never copy, paste, or adapt any PHP/JS/CSS from WP Rocket.
+1. **No code reuse.** Never copy, paste, or adapt PHP/JS/CSS from any existing performance plugin.
-2. **Feature specs only.** Document what WP Rocket does from a *user perspective* (UI behavior, options, output), not how it's implemented.
+2. **Feature specs only.** Features are specified from a *user perspective* (UI behavior, options, output), not from anyone's implementation.
 3. **Independent implementation.** All code written from scratch using WordPress APIs and standard libraries.
 4. **Documentation trail.** Keep records of the specification process to prove independent development.
 
 ### What We Study (User Perspective)
 
-- WP Rocket admin UI: what settings exist, what they control
+- Admin UIs of established performance plugins: what settings exist, what they control
 - Frontend output: what HTML/JS/CSS changes appear after activation
 - Behavior: when cache clears, what gets optimized, what's excluded by default
 - Performance: what metrics improve
@@ -204,8 +204,8 @@ wp-recache/
 ## Legal Considerations
 
 1. **Document everything.** Keep records of the specification process.
-2. **Never access WP Rocket source** while implementing.
+2. **Never access third-party plugin source code** while implementing.
-3. **Use different naming.** Don't use "rocket" prefixes or similar naming.
+3. **Use different naming.** Don't reuse prefixes or naming from existing plugins.
 4. **Independent architecture.** Design your own class structure.
 5. **Different defaults.** Choose different default settings where possible.
 
@@ -219,8 +219,8 @@ wp-recache/
 
 ## Success Criteria
 
-1. Feature parity with WP Rocket for page cache, file optimization, image optimization
+1. Feature set competitive with established commercial performance plugins: page cache, file optimization, image optimization
-2. No code overlap (verified by code review)
+2. No code overlap with any existing plugin (verified by code review)
-3. Performance benchmarks comparable to or better than WP Rocket
+3. Performance benchmarks comparable to or better than established commercial solutions
 4. Clean, maintainable code following WordPress standards
 5. Active open source community