Pass permission and sandbox CLI flags in build_claude_command

[geoffjay]

Context

Child of #78. Depends on #116.

Changes

Update build_claude_command() in manager.rs to emit Claude CLI flags from the new AgentConfig fields:

• --permission-mode <mode> when permission_mode is set
• --allowed-tools <tool> for each entry in allowed_tools
• --disallowed-tools <tool> for each entry in disallowed_tools
• --tools <tool1>,<tool2>,... when tools is non-empty
• --dangerously-skip-permissions when skip_permissions is true

Also update create_agent() in api.rs to map the new CreateAgentRequest fields into AgentConfig.

Files

• crates/orchestrator/src/manager.rs — build_claude_command()
• crates/orchestrator/src/api.rs — create_agent() handler

Acceptance Criteria

• All new fields are mapped from request to config in create_agent()
• build_claude_command() produces correct flag strings for all field combinations
• Flags are not emitted when fields are at their defaults (empty/false)
• cargo build --workspace passes