Phase 1: Success capture -- extend CapturedLearning with procedural memory

[AlexMikhalev]

Parent Epic

Part of #692 (Operational Skill Store)

Summary

Extend terraphim-agent learn from failure-only capture to also record successful multi-step workflows as reusable CapturedProcedure entries.

What Changes

New types in terraphim_types

• CapturedProcedure -- ordered list of steps with preconditions, postconditions, and confidence score
• ProcedureStep -- individual command with expected exit code, output pattern, timeout, required env vars

New capture path in terraphim_agent/src/learnings/

• Add capture_successful_procedure() alongside existing capture_failed_command()
• Accept session ID or manual step list as input
• Store as markdown (matching existing format) with structured frontmatter
• Index via RoleGraph (same as failure learnings)

CLI extensions

terraphim-agent learn capture-success "task-type" --steps-from-session <id>
terraphim-agent learn capture-success "task-type" --steps "cmd1" "cmd2" "cmd3"
terraphim-agent learn procedures
terraphim-agent learn procedures --task-type "deploy"

Affected Crates

• terraphim_agent (learnings module)
• terraphim_types (new types)

Dependencies

• Enhanced learning capture: multi-hook pipeline with importance scoring #599 Enhanced learning capture (multi-hook pipeline provides richer event data)

Acceptance Criteria

• CapturedProcedure type defined with serde + Persistable
• capture-success subcommand stores procedure to learnings directory
• procedures subcommand lists stored procedures with confidence scores
• Existing learn list and learn query also surface procedures
• Aho-Corasick deduplication prevents storing near-identical procedures
• Unit tests for capture, storage, and query paths