chore: point repo references at the plainlang org

The GitHub organization moved from Codeplain-ai to plainlang, so every
hardcoded `Codeplain-ai/plain-forge` string is now stale.

- package.json: repository.url, homepage, bugs.url — these ship inside the
  published tarball and drive the npm page's Repository link.
- bin/cli.mjs: the usage-guide link printed after install.
- scripts/deploy.sh: REPO, used by the workstation-publish path for the
  release lookup and the Deployments API call.
- RELEASING.md: the changelog-link template and the trusted-publisher row.

.github/workflows/publish.yml needs no change: it never hardcodes the org,
reaching for github.repository and github.server_url instead, and auth is
OIDC. The npm trusted-publisher entry has already been repointed.

The RELEASING.md link to Codeplain-ai/codeplain is left as-is — that repo
has not moved.

Author: zanjonke

RELEASING.md

@@ -84,7 +84,7 @@ with the changelog link last:
 
 - Refactors, CI, dependencies — things that don't change behaviour for users.
 
-**Full Changelog**: https://github.com/Codeplain-ai/plain-forge/compare/v1.0.20...v1.0.21
+**Full Changelog**: https://github.com/plainlang/plain-forge/compare/v1.0.20...v1.0.21
 ```
 
 Editing a release afterwards fires `release: edited`, not `published`, so fixing typos
@@ -114,7 +114,7 @@ at the repo root — gitignored, and the only place a webhook should live locall
 
 | what | where | note |
 |---|---|---|
-| Trusted publisher | npmjs.com → `plain-forge` → Settings → Trusted Publisher | GitHub Actions, `Codeplain-ai/plain-forge`, workflow `publish.yml` |
+| Trusted publisher | npmjs.com → `plain-forge` → Settings → Trusted Publisher | GitHub Actions, `plainlang/plain-forge`, workflow `publish.yml` |
 | `SLACK_WEBHOOK_URL` | repo secret | the only secret this repo has; notifications are skipped without it |
 | Branch protection | `main` | `Test (node 18 / 20 / 22)` required, no force pushes, no deletion |
 

bin/cli.mjs

@@ -1010,7 +1010,7 @@ function printNextSteps(agent) {
     `prerequisite: install the ${codeplain("codeplain")} CLI to render your specs into code — ${link("https://www.codeplain.ai/")}`,
   );
   console.log(
-    `usage guide: ${link("https://github.com/Codeplain-ai/plain-forge#usage")}`,
+    `usage guide: ${link("https://github.com/plainlang/plain-forge#usage")}`,
   );
   console.log();
 }

package.json

@@ -8,11 +8,11 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/Codeplain-ai/plain-forge.git"
+    "url": "git+https://github.com/plainlang/plain-forge.git"
   },
-  "homepage": "https://github.com/Codeplain-ai/plain-forge",
+  "homepage": "https://github.com/plainlang/plain-forge",
   "bugs": {
-    "url": "https://github.com/Codeplain-ai/plain-forge/issues"
+    "url": "https://github.com/plainlang/plain-forge/issues"
   },
   "license": "MIT",
   "keywords": [

scripts/deploy.sh

@@ -23,7 +23,7 @@ set -euo pipefail
 
 PKG="plain-forge"
 ENVIRONMENT="npm"
-REPO="Codeplain-ai/plain-forge"
+REPO="plainlang/plain-forge"
 
 TAG=""
 DRY_RUN=false