chore(release): bump to v0.19.0

- aibox.lock: v0.18.2 → v0.19.0
- CHANGELOG: finalize v0.19.0 section (dated 2026-04-22)
- src/PROVENANCE.toml: regenerate for v0.19.0 (693 files)

v0.19.0 is the TeamMember + 51-role catalog + Model artifacts + binding
routing refactor (three DECs: SpryTulip, BraveFalcon, LoyalComet).
Full details in CHANGELOG.md.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: claude

CHANGELOG.md

@@ -5,7 +5,7 @@ Versions follow [Semantic Versioning](https://semver.org/).
 
 ---
 
-## [v0.19.0-candidate] — unreleased
+## [v0.19.0] — 2026-04-22
 
 ### Added (v0.19.0 architecture refactor)
 

aibox.lock

@@ -4,7 +4,7 @@ synced_at = "2026-04-19T08:03:58.481219+00:00"
 
 [processkit]
 source = "https://github.com/projectious-work/processkit.git"
-version = "v0.18.2"
+version = "v0.19.0"
 src_path = "src"
 release_asset_sha256 = "3c6bf672e3a4ac2bf8c0b807c2e5fe948ff27906b6a0aa0ff73d36a1b2f7c98c"
 installed_at = "2026-04-19T08:03:58.481219+00:00"