Managed-agent reconciliation: supported repair for 46 personaOrphaned records

## Request

Please provide the supported Buzz Desktop workflow, command, or release that can reconcile 46 existing orphaned managed-agent records with staged agent definitions without creating new agent identities.

A supported solution could be:

1. In-place replace or rebind of the affected records.
2. Supported removal plus documented re-import that preserves required team references.
3. A vendor migration or reconciliation that repairs the records and team membership atomically.

## Observed state

- Buzz Desktop was updated through the official updater from 0.5.8 to 0.5.10.
- The Agents view shows Fizz, Honey, Bumble, plus `Unknown agents (46)`.
- All 46 affected records show `CONFIGURATION MISSING`.
- No agent has been started.
- The staged package contains 46 validated `buzz-agent` / `lm-studio` / `deepseek-v4-flash` definitions.
- The import preview states it creates a new independent agent with a fresh keypair and that the source identity does not transfer, so the import was cancelled.
- v0.5.10 exposes no supported edit, delete, remove, replace, or reconcile action for these affected records.
- We will not modify the managed-agent database, Keychain, or internal Tauri state as a workaround.

## Requested migration guarantees

Please state whether the supported repair changes keys, relay identities, team references, or running-agent state, and provide a supported backup and rollback procedure.

## Acceptance criteria

- Exactly 49 visible identities: the 46 Studio agents plus Fizz, Honey, and Bumble.
- Zero `CONFIGURATION MISSING` records.
- Apple Ecosystem Expert Team has its 8 expected members and Buzz Platform Integration has its 3 expected members, with no stale references.
- All agents remain stopped.
- No runtime, master, or external-action flag is enabled.

Start in the Buzz Desktop Agents view and the v0.5.10 import preview, then trace the managed-agent reconciliation or migration entry point; the payload names no source file or test. Verify whether a supported operation can preserve identities and team references, and use the stated acceptance criteria to determine when the repair is complete.

Written by the indexing model from the issue text.