Docs subtask: update GeneralUpdate.Bowl component documentation

[JusterZhu]

Parent: #45

Scope

Document GeneralUpdate.Bowl for post-upgrade startup monitoring and recovery.

Acceptance criteria

• Explains crash detection, backup restoration, dump/trace output, and lifecycle placement.
• Includes a practical setup flow and recovery scenario.
• Avoids firmware-specific recovery concepts.

[JusterZhu]

Completed via PR #58: GeneralUpdate.Bowl documentation has been rewritten covering lifecycle placement, crash detection, recovery flows, BowlContext parameters, and platform differences.