* docs(readme): refine repository watch section
Replace the Stay Tuned section with a clearer Watch EverOS call to action in both English and Chinese READMEs.
Remove the star GIF and keep star history as lighter social proof.
* docs(readme): improve highlights table spacing
Add spacing below each feature title in the EverOS highlights table.
Mirror the same table spacing in the Chinese README.
Rename the overview section to focus on why EverOS matters in both English and Chinese READMEs.
Simplify the EverMind ecosystem copy around EverOS as the core memory architecture and mirror that positioning in the Chinese README.
