Prepare RepoPrompt CE 1.0.13

[provencher]

Summary

• bump RepoPrompt CE to 1.0.13 (build 14)
• synchronize the bundled MCP helper version
• supersede the unpublished v1.0.12 draft with the PR Fix release helper initialization timeout crash #140 helper timeout fix included

Scope

• based on main at 8ae351b, including PR Fix release helper initialization timeout crash #140
• excludes PR Isolate core runtime and add headless foundation #118 / core isolation
• no local app installation or replacement

Validation

• independent pair-agent release review: no findings
• release metadata synchronization check
• release self-test and coordinated release preflight
• strict lint
• repoprompt-mcp build and version probe
• contribution commit and push preflights