chore: rebrand companion-os to clanker-agent

- Rename all package names from companion-* to clanker-*
- Update npm scopes from @mariozechner to @harivansh-afk
- Rename config directories .companion -> .clanker
- Rename environment variables COMPANION_* -> CLANKER_*
- Update all documentation, README files, and install scripts
- Rename package directories (companion-channels, companion-grind, companion-teams)
- Update GitHub URLs to harivansh-afk/clanker-agent
- Preserve full git history from companion-cloud monorepo

packages/agent/package.json

@@ -1,5 +1,5 @@
 {
-  "name": "@mariozechner/companion-agent-core",
+  "name": "@harivansh-afk/clanker-agent-core",
   "version": "0.56.2",
   "description": "General-purpose agent with transport abstraction, state management, and attachment support",
   "type": "module",
@@ -17,7 +17,7 @@
     "prepublishOnly": "npm run clean && npm run build"
   },
   "dependencies": {
-    "@mariozechner/companion-ai": "^0.56.2"
+    "@harivansh-afk/clanker-ai": "^0.56.2"
   },
   "keywords": [
     "ai",
@@ -30,7 +30,7 @@
   "license": "MIT",
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/getcompanion-ai/co-mono.git",
+    "url": "git+https://github.com/harivansh-afk/clanker-agent.git",
     "directory": "packages/agent"
   },
   "engines": {