chore: sync EPF wiki updates and zh translation

[AutoBot42]

Summary

• Sync weekly EPF wiki updates from upstream eth-protocol-fellows/protocol-studies into the Chinese fork.
• Preserve Chinese fork translations while absorbing compatible upstream metadata/template changes.
• Translate updated PR template checklist/instructions into Simplified Chinese.
• Keep the English spell-check workflow deleted to avoid false positives on Chinese content.

Verification

• git diff --check
• git grep -n -I -E '<<<<<<<|>>>>>>>' -- '*.md' '*.mdx' '*.txt' '*.yml' '*.yaml'

Conflict resolution

• Markdown/MDX/TXT/YAML conflicts: preferred existing Chinese content where semantically corresponding.
• Config/workflow conflict: preserved deletion of .github/workflows/spell-check.yml.