fix(plugin): bump to 0.1.19 so the hook fixes actually reach installs

c569cdd rewrote all four hook scripts and did not bump the manifest. The
version is what the installer compares, so `/plugin` reported "already at
the latest version (0.1.18)" and never refreshed its cache — the fix was
on main and unreachable.

Both halves of the install were observably out of step:

  ~/.claude/plugins/marketplaces/scribe-plugin  -> at 3284ac6, fixed
  ~/.claude/plugins/cache/.../scribe/0.1.18/    -> still lowercase env
                                                   vars and `jq -rR`

The clone pulls on its own; the CACHE is what executes, and it is only
re-copied when the version changes. So a plugin change without a bump
ships to the repo and stops there.

This is the #1040 lesson, already recorded in milestone #232's own
verification section ("Any `plugin/` change bumps `plugin.json` in the
same commit") and still missed — the rule was written down and not
followed. Nothing in CI enforces it, which is the same gap as #2204:
`plugin/**` triggers no workflow at all, so neither the missing bump nor
the broken scripts could be caught.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UaYUaouG9jjhATyuxCKrQs

plugin/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "scribe",
   "description": "Scribe system-of-record for Claude Code: MCP tools over your notes/tasks/projects/rules, a session-start push channel that surfaces your always-on rules + active-project context, process-skills (writing-plans, systematic-debugging, verification, brainstorming, reusing-code), and your saved Scribe Processes auto-surfaced as skills (/scribe:sync). Replaces superpowers + file-memory with one app-backed plugin.",
-  "version": "0.1.18",
+  "version": "0.1.19",
   "author": { "name": "Bryan Van Deusen" },
   "mcpServers": {
     "scribe": {