feat: finalize package presence branch and docs alignment

ROADMAP.md

@@ -143,7 +143,7 @@ ______________________________________________________________________
 | Hybrid retrieval | Semantic only, BM25 only, hybrid | Hybrid (BM25 keyword + cosine semantic) for best recall | ⬜ Pending |
 | Reranking | None, cross-encoder (`ms-marco-MiniLM`), LLM-as-judge | Cross-encoder rerank pass before prompt injection | ⬜ Pending |
 | Runbook format | Markdown, YAML, JSON | Markdown (human-editable, version-controllable) | ✅ Implemented |
-| Session index storage | Local `~/.tai/`, configurable path | `~/.tai/sessions/` with ChromaDB collection | ⬜ Pending |
+| Session index storage | Local `~/.tai/`, configurable path | `~/.tai/sessions/` with ChromaDB collection | ✅ Implemented (core) |
 
 ______________________________________________________________________
 
@@ -229,28 +229,30 @@ ______________________________________________________________________
 
 ### Tier 3 — Session Memory Index (institutional learning)
 
-Status: ⬜ Pending
+Status: ✅ Implemented (core retrieval/indexing) / ⬜ UX commands pending
 
 **Problem:** Every session starts from zero. Repeat incidents on the same host or
 same issue type get no benefit from past work.
 
-**Approach:**
+**Implemented now:**
 
 - On session end, embed the session summary (issue + root cause + actions) and upsert into a persistent ChromaDB collection (`~/.tai/sessions/`)
 - On session start, query for similar past sessions by issue text + hostname
 - Inject top-2 past sessions as `## Prior Sessions` context
-- Optionally: `/history` command in interactive mode to surface past sessions explicitly
+
+**Pending UX layer:**
+
+- `/history` command in interactive mode to surface past sessions explicitly
 
 **New module:** `src/tai/session_store.py`
 
 - `SessionStore`: wraps ChromaDB collection at `~/.tai/sessions/`
-- `index_session(session_log_path)` — embed and store completed session
-- `query_similar(issue, host, top_k) -> list[PastSession]`
+- `index_session(host, issue, summary, ai)` — embed and store completed session
+- `query(question, host, ai, top_k) -> list[PastSession]`
 
 **Changes to existing code:**
 
-- `session_log.py`: add `summarise() -> str` method (issue + final AI response)
-- `cli.py`: query `SessionStore` at session start, index at session end
+- `cli.py`: query `SessionStore` during analysis turns and index final responses at session end
 
 **Companion features buildable at same time:**
 
@@ -308,14 +310,14 @@ ______________________________________________________________________
 | Date | Decision | Outcome |
 |------|----------|---------|
 | 2026-05-04 | Implementation language | Python — with single distributable binary via Nuitka |
-| — | AI inference backend | vLLM (provisional) |
-| — | Default model | `gemma4:a4b` (provisional) |
+| 2026-05-04 | AI backend API | OpenAI-compatible API endpoint (local Ollama by default) |
+| 2026-05-04 | Default model | `gemma3:4b` |
 | 2026-05-04 | SSH auth methods | Keypair only (ed25519/RSA); auto-accept new hosts; reject on key change (MITM) |
 | 2026-05-04 | Bastion host support | `--jump-host` flag via SSH native ProxyJump |
 | 2026-05-04 | SSH config behavior | Use `~/.ssh/config` by default; allow override via `--ignore-ssh-config` |
 | 2026-05-04 | CLI vs interactive mode | Interactive: REPL for v0.1, `textual` TUI for v0.2+ |
-| 2026-05-04 | RAG embedding model | `nomic-embed-text` via Ollama (local, air-gapped safe) — ⬜ pending confirmation |
+| 2026-05-04 | RAG embedding model | `nomic-embed-text` via Ollama (local, air-gapped safe) |
 | 2026-05-04 | RAG vector store (Tier 1) | In-memory numpy cosine similarity — zero deps, session-scoped |
-| 2026-05-04 | RAG vector store (Tier 2/3) | `chromadb` embedded mode (default) or `qdrant` self-hosted — ⬜ pending confirmation |
+| 2026-05-04 | RAG vector store (Tier 2/3) | `chromadb` embedded mode (default) or `qdrant` self-hosted |
 | 2026-05-04 | RAG chunking unit | Command-boundary splitting — each collected command = one or more chunks |
 | 2026-05-04 | Runbook format | Markdown with YAML frontmatter, version-controlled in `runbooks/` directory |