fix: Replace Codeberg dependency with local Forgejo instance (#611)

- Add setup_forge() to bin/disinto: provisions Forgejo via Docker,
  creates admin + bot users (dev-bot, review-bot), generates API
  tokens, creates repo, and pushes code — all automated
- Rename env vars: CODEBERG_TOKEN→FORGE_TOKEN, REVIEW_BOT_TOKEN→
  FORGE_REVIEW_TOKEN, CODEBERG_REPO→FORGE_REPO, CODEBERG_API→
  FORGE_API, CODEBERG_WEB→FORGE_WEB, CODEBERG_BOT_USERNAMES→
  FORGE_BOT_USERNAMES (with backwards-compat fallbacks)
- Rename API helpers: codeberg_api()→forge_api(), codeberg_api_all()
  →forge_api_all() (with compat aliases)
- Add forge_url field to project TOML; load-project.sh derives
  FORGE_API/FORGE_WEB from forge_url + repo
- Update parse_repo_slug() to accept any host URL, not just codeberg
- Forgejo data stored under ~/.disinto/forgejo/ (not in factory repo)
- Update all 58 files: agent scripts, formulas, docs, site HTML

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

projects/disinto.toml.example

@@ -1,10 +1,11 @@
 # projects/disinto.toml.example — Template for disinto self-management
 #
 # Copy to projects/disinto.toml and fill in box-specific values,
-# or run: disinto init https://codeberg.org/johba/disinto
+# or run: disinto init johba/disinto
 
 name            = "disinto"
 repo            = "johba/disinto"
+forge_url       = "http://localhost:3000"
 repo_root       = "/home/YOU/dark-factory"
 primary_branch  = "main"