migrate to decoupled Blowfish layout, fix TOC scrollspy, and update docs

- Theme Decoupling & Cleanup:
      - Fully decoupled and vendored the Blowfish theme directly into root directories (layouts/,
  assets/, static/, data/, i18n/).
      - De-registered and cleaned up legacy Git submodules (themes/blowfish, themes/hugo-admonitions)
  from the Git index to protect the build from upstream breakages.
      - Configured .gitignore to ignore development preview symlinks (content, static,
  config/_default/menus.en.toml), build folders (public/, resources/), and locks.

    - TOC & Layout Fixes:
      - Replaced the custom layouts/_default/single.html template with the Blowfish default to restore
  native container widths and the side-by-side flex layout.
      - Restored TOC to float on the right sidebar on desktop viewports and render inline on mobile
  viewports.
      - Fixed a parameter resolution bug in layouts/partials/toc.html by checking both .Site.Params.
  smartTOC and .Site.Params.article.smartTOC (where it is defined in params.toml).
      - Upgraded the TOC scrollspy JavaScript to target all '#TableOfContents' containers on the page,
  enabling highlight tracking on both desktop and mobile layouts.

    - Documentation Updates (README.md):
      - Restored YAML front matter metadata block at the top.
      - Added detailed notes on the CI/CD build process and Gitea runner deployment targets
  (/srv/www/docs-public and /srv/www/docs-private).
      - Added a categorized and sorted "Shortcodes Quick Reference" table at the top of the shortcodes
  section (ordered by Custom, Hugo Default, and Blowfish).
      - Documented custom shortcodes (Include, Screenshot, Raw HTML) and missing Hugo default
  shortcodes (Highlight, Instagram, Param, Ref, Relref, Twitter, Vimeo, Youtube).
      - Restructured headings to ensure all sub-shortcodes are H3, removed block break tags (<br/>),
  and appended horizontal separators (---) after H2 sections.

i18n/ko.yaml

@@ -0,0 +1,81 @@
+global:
+  language: "KO"
+
+article:
+  anchor_label: "앵커"
+  date: "{{ .Date }}"
+  date_updated: "업데이트 날짜: {{ .Date }}"
+  draft: "초안"
+  edit_title: "내용 편집"
+  reading_time:
+    one: "{{ .Count }} 분"
+    other: "{{ .Count }} 분"
+  reading_time_title: "읽는 시간"
+  table_of_contents: "목차"
+  word_count:
+    one: "{{ .Count }} 단어수"
+    other: "{{ .Count }} 단어수"
+  views:
+    one: "{{ .Count }} 조회수"
+    other: "{{ .Count }} 조회수"
+  likes:
+    one: "{{ .Count }} 좋아요"
+    other: "{{ .Count }} 좋아요"
+  part_of_series: "이 글은 시리즈의 일부입니다."
+  part: "부분"
+  this_article: "이 글"
+  related_articles: "관련 글"
+  reply_by_email: "이메일로 답장"
+  reply_to: "{{ .Title }}에 대한 답장"
+
+a11y:
+  title: "접근성 설정"
+  disable_blur: "흐림 효과 끄기"
+  disable_images: "이미지 끄기"
+  show_link_underline: "링크 밑줄 표시"
+  font_size: "글꼴 크기"
+
+author:
+  byline_title: "작성자"
+
+code:
+  copy: "복사"
+  copied: "복사되었습니다"
+
+error:
+  404_title: "페이지를 찾을 수 없습니다 :confused:"
+  404_error: "오류 404"
+  404_description: "요청하신 페이지를 찾을 수 없습니다."
+
+footer:
+  dark_appearance: "다크 모드로 전환"
+  light_appearance: "라이트 모드로 전환"
+  powered_by: "{{ .Hugo }} & {{ .Theme }} 로 제공됨"
+
+list:
+  externalurl_title: "외부 사이트로 링크"
+  no_articles: "아직 게시된 글이 없습니다."
+
+nav:
+  scroll_to_top_title: "맨 위로 스크롤"
+  skip_to_main: "본문으로 건너뛰기"
+
+search:
+  open_button_title: "검색하기 (/)"
+  close_button_title: "닫기 (Esc)"
+  input_placeholder: "검색"
+
+sharing:
+  email: "이메일로 전송"
+  facebook: "Facebook에서 공유"
+  line: "LINE에 공유하기"
+  linkedin: "LinkedIn에서 공유"
+  pinterest: "Pinterest에 고정"
+  reddit: "Reddit에 게시"
+  twitter: "Twitter에 트윗"
+
+shortcode:
+  recent_articles: "최근 글"
+
+recent:
+  show_more: "더 보기"