Clone Strategy full-clone baseline

[BramVR]

Parent

#70

What to build

Add an explicit Clone Strategy shape and route current hydrate and agent prepare clone behavior through it using the existing full-clone behavior as the first adapter. Record selected strategy in the Agent Run Contract for agent handoff.

Acceptance criteria

• hydrate and agent prepare use an explicit full-clone strategy adapter.
• Existing clone behavior remains user-visible compatible.
• Agent Run Contract records selected clone strategy for prepared workspaces.
• Tests cover strategy selection, clone failure diagnostics, and redaction.
• Docs name full clone as current baseline and partial/sparse as later opt-ins.

Blocked by

• Git Operations and Project identity locality #71
• Agent Run Contract v1 baseline #73