feat(agent): add shared_learning module from PR #185 (disabled, needs persistence refactor)

Cherry-picked shared_learning/ directory from PR #185 branch. The store.rs
uses sqlx directly which violates project architecture -- it must be
refactored to use terraphim_persistence as the storage layer.

The module is commented out in lib.rs until the refactor is complete.
mention.rs and persona.rs changes from PR #185 were NOT merged because
they conflict with the current NormalizedTerm API (u64 vs String IDs).

Refs #185

Author: AlexMikhalev

crates/terraphim_agent/Cargo.toml

@@ -58,6 +58,8 @@ chrono = { workspace = true }
 strsim = "0.11"  # For edit distance / fuzzy matching in forgiving CLI
 uuid = { workspace = true }
 dialoguer = "0.12"  # Interactive CLI prompts for onboarding wizard
+# TODO: shared_learning needs refactor to use terraphim_persistence instead of direct sqlx
+# sqlx = { version = "0.8", features = ["runtime-tokio", "sqlite", "chrono"] }
 
 # REPL dependencies - only compiled with features
 rustyline = { version = "17.0", optional = true }

crates/terraphim_agent/src/lib.rs

@@ -1,6 +1,9 @@
 pub mod client;
 pub mod onboarding;
 pub mod service;
+// TODO: shared_learning needs refactor to use terraphim_persistence instead of direct sqlx
+// #[cfg(feature = "shared-learning")]
+// pub mod shared_learning;
 pub mod tui_backend;
 
 // Robot mode - always available for AI agent integration

crates/terraphim_agent/src/shared_learning/mod.rs

@@ -0,0 +1,27 @@
+//! Shared Learning System for Terraphim AI
+//!
+//! This module provides a shared learning store that aggregates learnings
+//! across agents, deduplicates using BM25, and promotes learnings based on
+//! trust levels (L1/L2/L3) with Gitea wiki synchronization.
+//!
+//! # Architecture
+//!
+//! ```text
+//! Learning Capture → BM25 Deduplication → Trust Promotion → Gitea Wiki Sync
+//!        ↓                    ↓                  ↓                  ↓
+//!  Multiple Sources    Merge Duplicates   L1→L2→L3          Wiki Pages
+//! ```
+//!
+//! # Trust Levels
+//!
+//! - **L1 (Unverified)**: Auto-captured from various sources, advisory only
+//! - **L2 (Peer-Validated)**: Applied 3+ times across 2+ agents with positive outcome
+//! - **L3 (Human-Approved)**: CTO review via `/evolve` or Gitea issue approval
+
+mod store;
+mod types;
+mod wiki_sync;
+
+pub use store::{SharedLearningStore, StoreConfig};
+pub use types::{SharedLearning, TrustLevel};
+pub use wiki_sync::{GiteaWikiClient, WikiSyncError};