docs: revamp the README in English and Nepali

[voidash]

What changed

Rewrites README.md and README.ne.md so they describe the project as it is, in both languages.

• What the project is, its status and the Apache-2.0 licence, with a link between the two languages.
• Run it with Docker: a Docker-only path. It covers the OAuth App, .env.local, docker compose up -d --build, and docker compose run --rm migrate node scripts/init-project.js. It points to prod-docker-compose.yaml and the Dokploy guide for production.
• Develop locally: the Bun path, with the setup order corrected in docs: correct setup and design documentation #27.
• Configuration, Commands, How it is built (stack, layout, API contract, members, privacy and security).
• Contributing: points to CONTRIBUTING, docs/CONVENTIONS, the code of conduct, governance, SECURITY, the PRD and PRIVACY from docs: establish contribution and product foundations #42.

Also:

• Removed duplication: the REST route table (now a link to openapi.yaml) and the separate Ports and test-coverage sections.
• Fixed inaccuracies:
  • The old README said the pages are server-rendered, but the public pages load their data in the browser.
  • For a non-public profile, it is the API that returns 404; the page shows "Profile not available".
  • The branch workflow described the personal repository's rules.
  • README.ne.md said the project was still in "documentation and planning" with "no runnable application".

Closes #39

Merge after #53. The Docker commands (node scripts/..., .env support, prod-docker-compose.yaml) come from it.

Contract impact

• No changes to packages/api-contract

Checks

• Documentation only; CI passes.
• Every factual claim checked against the code: env variables (config.ts, .env.example), commands (package.json), setup steps (scripts/setup.ts), rate-limited routes, GITHUB_TOKEN use, visibility and avatar behaviour, CI steps.
• Every relative link resolves, and every table-of-contents anchor resolves under GitHub's own slug rules (github-slugger), Nepali headings included.
• English and Nepali agree in structure: the same 7 sections, all 11 configuration rows, all 14 code blocks, and identical commands.

Notes for reviewers

The Nepali text needs a native-speaker review, as the PRD requires for every Nepali string. Commands, file paths and setting names stay in English in both versions.

Foundation checklist

• Commits signed off (git commit -s)
• Works in both English and Nepali where applicable
• No secrets or real personal data anywhere in the diff
• Documentation updated; English and Nepali versions agree where both exist

[abhiyandhakal]

LGTM.
But merge conflicts need to be resolved before merge.