[codex] Add ClawWatch demo command coverage

[ThinkOffApp]

What changed

• Adds reliable local handlers for the live demo prompts: GroupMind room status, room posting, Berlin weather, and today event context.
• Adds watch-side phone/Oura vitals storage via Wear Data Layer /clawwatch/vitals and includes fresh phone vitals in Health/Google Health summaries.
• Adds live pulse measurement with Health Connect heart-rate write support and documents the phone companion payload contract.
• Expands config sync aliases for groupmind/clawhub keys and rooms so existing companion configs can hydrate room access.

Validation

• ./gradlew :app:assembleDebug
• Installed the debug APK on the paired device at 192.168.0.184:37837 before ADB dropped.
• Verified ClawWatch migrated legacy GroupMind prefs into secure prefs on launch.
• Smoke-tested the GroupMind read and write API path with the same X-API-Key header ClawWatch uses.

Notes

• WRITE_HEART_RATE was added but was not granted by the time ADB disconnected; the watch should prompt on first write-pulse use if not pre-granted.
• Phone/Oura requires the private phone companion to send /clawwatch/vitals; this PR implements the public watch-side receiver and summary path.