Feat v0.7.11 query & HTTP ergonomics

Add four new Starlark sandbox builtins to reduce extension friction
around SQL decomposition and synchronous HTTP fan-out:

- db.count(table, filters) — integer row count
- db.aggregate(table, column, op, filters) — single-value aggregation
- db.query_batch(queries) — up to 10 query specs in one call
- http.batch(requests) — concurrent dispatch of up to 10 HTTP requests

Extract buildSelectQuery helper from dbQuery for reuse by query_batch.
21 new tests (14 db, 7 http). No new permissions or schema changes.

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

ROADMAP.md

@@ -1,6 +1,6 @@
 # Armature — Roadmap
 
-## Current: v0.7.10 — Workflow Handoff + Assignment UI
+## Current: v0.7.11 — Query & HTTP Ergonomics
 
 Self-hosted extensible platform kernel. Auth, identity, packages, Starlark
 sandbox, storage, realtime, and ops are kernel primitives. Everything else
@@ -350,11 +350,11 @@ remaining friction points for extensions migrating from native Go/Python.
 
 | Step | Status | Description |
 |------|--------|-------------|
-| `db.count()` | | `db.count(table, filters={})` → int. `SELECT count(*) FROM ext_{pkg}_{table} WHERE ...`. Uses existing `starlarkFiltersToSQL` builder. Permission: `db.read`. ~40 lines in `db_module.go`. |
-| `db.aggregate()` | | `db.aggregate(table, column, op, filters={})` → single value. `op` ∈ {`count`, `sum`, `avg`, `min`, `max`}. Column name validated same as filter keys. Returns int/float/None. Permission: `db.read`. ~60 lines in `db_module.go`. |
-| `db.query_batch()` | | `db.query_batch(queries)` → list of result sets. Each query spec is a dict with `table` (required), `filters`, `order`, `limit`, `before`, `after`, `search_like` (all optional, same as `db.query`). Loops existing query builder internally — one Starlark↔Go boundary crossing instead of N. Permission: `db.read`. ~30 lines in `db_module.go`. |
-| `http.batch()` | | `http.batch(requests)` → list of response dicts (ordered). Each request dict: `method`, `url`, `body`, `headers`. Concurrent dispatch via goroutines capped at 10, `sync.WaitGroup` collection. Reuses existing `httpDo` plumbing (SSRF checks, domain allowlist, body cap, timeout). Individual failures return error response dicts, don't abort batch. Permission: `api.http`. ~80 lines in `http_module.go`. |
-| Tests | | Unit tests for all four builtins. `db.count`/`db.aggregate` test empty table, filtered, type coercion. `db.query_batch` test mixed specs, empty list. `http.batch` test concurrent execution, partial failure, ordering. PG + SQLite for db tests. |
+| `db.count()` | done | `db.count(table, filters={})` → int. `SELECT count(*) FROM ext_{pkg}_{table} WHERE ...`. Uses existing `starlarkFiltersToSQL` builder. Permission: `db.read`. |
+| `db.aggregate()` | done | `db.aggregate(table, column, op, filters={})` → single value. `op` ∈ {`count`, `sum`, `avg`, `min`, `max`}. Column name validated same as filter keys. Returns int/float/None. Permission: `db.read`. |
+| `db.query_batch()` | done | `db.query_batch(queries)` → list of result sets. Each query spec is a dict with `table` (required), `filters`, `order`, `limit`, `before`, `after`, `search_like` (all optional, same as `db.query`). Loops extracted `buildSelectQuery` helper internally. Permission: `db.read`. |
+| `http.batch()` | done | `http.batch(requests)` → list of response dicts (ordered). Each request dict: `method`, `url`, `body`, `headers`. Concurrent dispatch via goroutines capped at 10, `sync.WaitGroup` collection. Reuses existing `executeHTTPRequest` plumbing (SSRF checks, domain allowlist, body cap, timeout). Individual failures return error response dicts, don't abort batch. Permission: `api.http`. |
+| Tests | done | 21 new tests (14 db, 7 http). `db.count`/`db.aggregate` test empty table, filtered, type coercion, invalid op/column. `db.query_batch` test mixed specs, empty list, cap, missing table. `http.batch` test blocked domains, partial failure, mixed results, input validation. |
 
 ### v0.7.12 — Concurrent Execution Primitive (was v0.7.11)