Phase 17: Model profiles + scoped search — the LLM-brain keystone

Implements PRD invariant 9 ("every reader gets its own profile") and
completes the multi-model substrate vision. Local models (or agents)
bind to a named set of datasets; activation pre-loads their vector
indexes into memory; search enforces scope.

Schema (shared::types):
- ModelProfile { id, ollama_name, description, bound_datasets,
                 hnsw_config, embed_model, created_at, created_by }
- ProfileHnswConfig mirrors vectord::trial::HnswConfig to avoid a
  cross-crate dep cycle. Default (ec=80, es=30) matches the Phase 15
  trial winner.
- bound_datasets can reference raw dataset names OR AiView names
  (both register as DataFusion tables with the same name, so mixing
  raw tables and PII-redacted views composes naturally)

Catalog (catalogd::registry):
- put_profile validates id is a slug (alphanumeric + -_ only) and
  every binding resolves to an existing dataset or view
- Persistence at _catalog/profiles/{id}.json, loaded on rebuild
- get_profile / list_profiles / delete_profile

HTTP endpoints:
- POST /catalog/profiles  (create/update)
- GET  /catalog/profiles  (list)
- GET/DELETE /catalog/profiles/{id}
- POST /vectors/profile/{id}/activate  (HNSW hot-load)
- POST /vectors/profile/{id}/search    (scope-enforced)

Activation (vectord::service::activate_profile):
- For each bound dataset, find vector indexes with matching source
- Pre-load embeddings into EmbeddingCache
- Build HNSW with profile's config
- Report warmed indexes + per-binding failures + duration
- Failures on individual bindings don't abort — "substrate keeps
  working" per ADR-017

Scoped search (vectord::service::profile_scoped_search):
- Look up profile, verify index.source ∈ profile.bound_datasets
- Returns 403 with allowed bindings list if out-of-scope
- Uses HNSW if index is warm, brute-force cosine otherwise (graceful
  degradation — no "must activate first" friction)

Bug fix surfaced during testing: vectord::refresh::try_update_index_meta
was a no-op for first-time indexes, so threat_intel_v1 and
kb_team_runs_v1 (both built via refresh after Phase C shipped) didn't
show up in the index registry. Now it auto-infers the source from the
index name convention (`{source}_vN`) and registers new metadata with
reasonable defaults.

End-to-end verified:
- Created security-analyst profile bound to [threat_intel]
- POST /vectors/profile/security-analyst/activate → warmed
  threat_intel_v1 (54 vectors) in 156ms, HNSW built
- Within-scope search: method=hnsw, returned relevant IP indicators
- Out-of-scope: tried to search resumes_100k_v2 (source=candidates)
  → 403 "profile 'security-analyst' is not bound to 'candidates' —
    allowed bindings: [\"threat_intel\"]"
- staffing-recruiter profile created bound to candidates + placements;
  search without activation fell through to brute_force (graceful)

Deferred (Phase 17 followups):
- VRAM-aware activation (unload-then-load via Ollama keep_alive=0)
  — Ollama already handles this; we don't need to reinvent
- Model-identity in audit trail — Phase 13 has role-based audit;
  adding model_id is ~20 LOC when we want it
- Profile bucket pre-load (profile:user bucket mount) — Phase 17.5

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/shared/src/types.rs

@@ -196,6 +196,69 @@ pub struct AiView {
     pub description: String,
 }
 
+/// Per-model configuration for HNSW builds. Declared inline so the PRD
+/// invariant 9 ("every reader gets its own profile") can carry tuning
+/// preferences without forcing a round-trip to vectord's trial system.
+/// Mirrors `vectord::trial::HnswConfig` to avoid a cross-crate dep cycle.
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+pub struct ProfileHnswConfig {
+    pub ef_construction: usize,
+    pub ef_search: usize,
+    #[serde(default)]
+    pub seed: Option<u64>,
+}
+
+impl Default for ProfileHnswConfig {
+    /// Matches the production HNSW default from Phase 15 trial sweep
+    /// (see docs/ADR and vectord::trial::HnswConfig::default).
+    fn default() -> Self {
+        Self { ef_construction: 80, ef_search: 30, seed: None }
+    }
+}
+
+/// A named client of the substrate — a local LLM, an AI agent, or a
+/// human role that should see a specific scoped view of the data.
+/// Profiles are the first-class "every reader gets its own profile"
+/// concept from PRD invariant 9.
+///
+/// Bound datasets can be raw catalog tables OR `AiView` names — either
+/// works at query time since both register as DataFusion tables with
+/// the same name. Mixing raw and views lets you compose access rules:
+/// bind a model to `candidates_safe` (PII-redacted view) and `placements`
+/// (raw table, no PII), and the model gets exactly what it needs.
+///
+/// Stored at `_catalog/profiles/{id}.json`. Activation (`/profile/{id}/
+/// activate`) pre-loads the embedding cache and builds HNSW with the
+/// profile's config — first search after activate is warm.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct ModelProfile {
+    /// Unique id — slug form (alphanumeric + `-`, `_`). Used in URLs,
+    /// bucket names (`profile:{id}`), and trial journal prefixes.
+    pub id: String,
+    /// Ollama model tag (e.g. "qwen2.5:7b", "nomic-embed-text:latest").
+    /// Used when this profile is the "generate" or "embed" caller.
+    pub ollama_name: String,
+    /// Free-text description surfaced to operators. Who/what is this
+    /// profile for?
+    #[serde(default)]
+    pub description: String,
+    /// Names of datasets or AiViews this profile can read. A search
+    /// against an index whose `source` isn't in this list is refused.
+    pub bound_datasets: Vec<String>,
+    /// Per-profile HNSW config, used when activate builds the graph.
+    #[serde(default)]
+    pub hnsw_config: ProfileHnswConfig,
+    /// Which embedding model this profile expects. Defaults to
+    /// `nomic-embed-text` (the only one currently installed).
+    #[serde(default = "default_embed_model")]
+    pub embed_model: String,
+    pub created_at: chrono::DateTime<chrono::Utc>,
+    #[serde(default)]
+    pub created_by: String,
+}
+
+fn default_embed_model() -> String { "nomic-embed-text".to_string() }
+
 /// Soft-delete marker (Phase E).
 ///
 /// Tombstones live beside the dataset in `_catalog/tombstones/{dataset}/`