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/clanker-grind/README.md

@@ -0,0 +1,45 @@
+# clanker-grind
+
+Explicit grind mode for clanker.
+
+Features:
+
+- Auto-activates only when the user uses explicit grind cues in a prompt
+- Persists run state in session custom entries
+- Continues work on a heartbeat while running in `clanker daemon`
+- Pauses automatically when the user sends a normal prompt
+
+Example prompts:
+
+- `Keep going on this until 5pm`
+- `Don't stop until the refactor is done`
+
+Commands:
+
+- `/grind start --until "5pm" Ship the refactor`
+- `/grind status`
+- `/grind pause`
+- `/grind resume`
+- `/grind stop`
+
+Settings:
+
+```json
+{
+  "clanker-grind": {
+    "enabled": true,
+    "pollIntervalMs": 30000,
+    "cueMode": "explicit-only",
+    "requireDaemon": true,
+    "userIntervention": "pause",
+    "cuePatterns": [
+      "don't stop",
+      "keep going",
+      "keep running",
+      "run until",
+      "until done",
+      "stay on this until"
+    ]
+  }
+}
+```