docs(readme): document project-bootstrap usage

Both README.md and README.ru.md gain a new "Using skills in projects"
/ "Использование в проектах" subsection right after the install
quick-start. Briefly describes what `project-bootstrap` lays down
(git, .gitignore, README, .wiki/, .tasks/, CLAUDE.md, manifest,
superpowers-plugin check) and the init/upgrade dual mode.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.wiki/log.md

@@ -29,3 +29,4 @@ Parseable: `grep "^## \[" .wiki/log.md | tail -20`.
 ## [2026-04-28] cleanup | removed stale `~/.claude/skills/{wiki-maintainer,task-status-wiki}/` installs (replaced by `using-wiki`/`using-tasks`); 16 skills installed, no duplicates; context7 plugin (mcp__plugin_context7_context7__*) confirmed live after restart
 ## [2026-04-28] decision | install-portability — `install.sh`/`build.sh` patched to drop `mapfile`+`find -printf`; stock macOS (bash 3.2 + BSD find) now works; verified on git-bash (16 skills discovered, sorted, installed; build.sh produces archive)
 ## [2026-04-28] decision | project-bootstrap@1.1.0 — added Step 5.6: detects `superpowers@claude-plugins-official` via `~/.claude/plugins/installed_plugins.json` and prints install command + upstream link if missing; chat-only, never auto-installs (slash commands aren't callable from a skill, and silent plugin install is overreach)
+## [2026-04-28] doc | README.md + README.ru.md — new "Using skills in projects" / "Использование в проектах" section after install quick-start; describes project-bootstrap workflow (git, .gitignore, README, .wiki/, .tasks/, CLAUDE.md, manifest, superpowers-plugin check) and the init/upgrade modes