feat: add V2 service publishing and username claiming APIs

- Add POST /services endpoint for publishing services with username verification
- Add DELETE /services/:serviceId endpoint for unpublishing services
- Add GET /services/:serviceFqn endpoint for service discovery
- Add POST /usernames/claim endpoint with Ed25519 signature verification
- Add POST /usernames/renew endpoint for extending username TTL
- Add GET /usernames/:username endpoint for checking username availability
- Add username expiry tracking and cleanup (365-day default TTL)
- Add service-to-offer relationship tracking
- Add signature verification for username operations
- Update storage schema for usernames and services tables
- Add comprehensive README documentation for V2 APIs
- Update version to 0.8.0

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

package-lock.json

@@ -1,14 +1,15 @@
 {
   "name": "@xtr-dev/rondevu-server",
-  "version": "0.1.4",
+  "version": "0.1.5",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@xtr-dev/rondevu-server",
-      "version": "0.1.4",
+      "version": "0.1.5",
       "dependencies": {
         "@hono/node-server": "^1.19.6",
+        "@noble/ed25519": "^3.0.0",
         "better-sqlite3": "^12.4.1",
         "hono": "^4.10.4"
       },
@@ -523,6 +524,15 @@
         "@jridgewell/sourcemap-codec": "^1.4.10"
       }
     },
+    "node_modules/@noble/ed25519": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/@noble/ed25519/-/ed25519-3.0.0.tgz",
+      "integrity": "sha512-QyteqMNm0GLqfa5SoYbSC3+Pvykwpn95Zgth4MFVSMKBB75ELl9tX1LAVsN4c3HXOrakHsF2gL4zWDAYCcsnzg==",
+      "license": "MIT",
+      "funding": {
+        "url": "https://paulmillr.com/funding/"
+      }
+    },
     "node_modules/@tsconfig/node10": {
       "version": "1.0.12",
       "resolved": "https://registry.npmjs.org/@tsconfig/node10/-/node10-1.0.12.tgz",