feat: encrypted secrets vault across CLI, desktop, dashboard, and backend

Local vault (apps/cli): clean-room PRMVLT01 format — Argon2id →
XChaCha20-Poly1305, AEAD-bound header, atomic writes. vault:* / secrets:*
/ inject (primora:// refs) / agent credential broker (dummy tokens in the
child, real secret on the wire) / TTL sessions / stack:* operator group.

Project vault (backend): core.project_secrets, AES-256-GCM via the
platform encryptor. Metadata-only list, audit-logged reveal, and
secret://NAME refs resolved at job delivery — refs stored, values never.

Surfaces: dashboard Vault page (+ local-vault card under the Tauri
shell), desktop vault window via IPC to the primora binary,
secrets:* --remote CLI mode, metadata/write-only MCP tools so agents
consume secrets via secret:// refs without holding plaintext.

Authored By: TDvorak <[email protected]>

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/cli/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@primora/cli",
-  "version": "0.5.0",
+  "version": "0.6.0",
   "description": "Primora command-line client",
   "type": "module",
   "bin": {
@@ -19,6 +19,8 @@
   },
   "dependencies": {
     "@clack/prompts": "^1.8.1",
+    "@noble/ciphers": "^2.4.0",
+    "@noble/hashes": "^2.4.0",
     "cac": "^7.0.0",
     "picocolors": "^1.1.1"
   },