feat(pastebin): add pastebin web app

[dschmidt]

Summary

A code sharing app for OpenCloud. Users can create pastebins with multiple files, share them via public links, and view them with syntax highlighting.

pastebin-demo.mp4

Features

• Create pastebins with multiple named files and optional title
• Syntax highlighting for 13+ languages (JS, TS, Python, Go, Rust, JSON, YAML, CSS, HTML, Bash, Markdown, SQL, and plaintext) via highlight.js
• Public link sharing with password support — uses ODS password input with policy validation and generator when the server enforces passwords
• Edit existing pastebins: add, rename, delete files, modify content
• List view with delete, sorted by newest first
• Per-file anchor links with scrollTo query param for deep linking into specific files
• Copy content and download raw file buttons per file
• Read-only mode support — hides edit controls when user only has view permissions
• Context route integration — closing the app editor returns to the pastebin list instead of the home directory
• All user-facing strings wrapped in $gettext() for i18n
• Locale-aware date formatting via web-pkg Luxon helpers

Storage format

~/.space/pastebin/
  <timestamp>-<slug>.ocpb/
    manifest.json          # { title: "..." }
    revisions/
      0/
        file1.py
        file2.js

Test plan

E2e tests with a PastebinPage page object (support/pages/pastebinPage.ts):

• Create: single file, with title, multi-file, empty content rejected, remove file editor
• List: shows pastebins, empty state, click navigates to view, delete from list
• Edit: loads content, edit and save, add file, rename file, cancel
• View: syntax highlighting, copy button, delete from view
• Public links: link icon in header, anchor scrollTo params, unauthenticated access with password handling
• Navigation: breadcrumb, view↔edit round trip, new button, close button returns to list (from create, from list, from edit)

Tests pass with and without server-enforced link passwords.

[JammingBen]

I'm gonna be honest, this is way cooler than I thought it would be 😄 Awesome stuff, really!

I left a bunch of comments, mostly minor stuff though, some things might even be suitable for a follow up.