chore(release): bump to v0.4.0 — forge schema + sigstore + admin proposal

Three forward-looking additions that warrant a minor bump:

- registry.json schema gains an optional `forge` field per version
  (Phase D, Round 3 #19); v0.5 wires per-forge fetchers
- Sigstore signing scaffold via opt-in [sigstore] extras (Phase F,
  Round 2 #16); fail-loud NotImplementedError until the
  key-management ADR lands
- REPO-PROPOSAL-admin.md captures the sibling Laravel admin repo
  bootstrap (Phase M, Round 4 #23)

118 tests pass; build clean: get_installer-0.4.0-py3-none-any.whl
+ get_installer-0.4.0.tar.gz.

Author: imanimanyara

CHANGELOG.md

@@ -6,6 +6,31 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 
 ## [Unreleased]
 
+## [0.4.0] - 2026-05-16
+
+### Added
+
+- **`forge` field in registry.json schema** (Phase D, Round 3 #19):
+  optional `forge: {type, owner, repo, release_tag_template,
+  asset_pattern}` block per version. Informational today; v0.5 wires
+  per-forge fetchers (GitHub Releases, GitLab Releases, Codeberg,
+  Gitea). Backward-compatible.
+- **Sigstore signing scaffold** (Phase F, Round 2 #16): new
+  `[sigstore]` opt-in extras + `verify.sign_bundle_with_sigstore`
+  skeleton. Dry-run returns the planned .sigstore path; apply
+  raises NotImplementedError pointing at the pending
+  key-management ADR.
+- **REPO-PROPOSAL-admin.md** (Phase M, Round 4 #23): scope, stack,
+  routes, and bootstrap checklist for the sibling
+  `simtabi/get-installer-admin` Laravel repo when someone takes
+  that on.
+
+### Why minor not patch
+
+The `forge` schema field is a backward-compatible addition but
+opens the door for a class of new fetchers, so minor is the
+appropriate semver bump.
+
 ## [0.3.2] - 2026-05-16
 
 ### Fixed — release workflow

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "get-installer"
-version = "0.3.2"
+version = "0.4.0"
 description = "Reusable, registry-driven curl-pipe-sh-style installer for distributing dev tools across public, private, enterprise, and government contexts."
 readme = "README.md"
 license = { file = "LICENSE" }