Phase 6: Ingest pipeline — CSV, JSON, PDF, text file support

- ingestd crate: detect file type → parse → schema detection → Parquet → catalog
- CSV: auto-detect column types (int, float, bool, string), handles $, %, commas
  Strips dollar signs from amounts, flexible row parsing, sanitized column names
- JSON: array or newline-delimited, nested object flattening (a.b.c → a_b_c)
- PDF: text extraction via lopdf, one row per page (source_file, page_number, text)
- Text/SMS: line-based ingestion with line numbers
- Dedup: SHA-256 content hash, re-ingest same file = no-op
- Gateway: POST /ingest/file multipart upload, 256MB body limit
- Schema detection per ADR-010: ambiguous types default to String
- 12 unit tests passing (CSV parsing, JSON flattening, type inference, dedup)
- Tested: messy CSV with missing data, dollar amounts, N/A values → queryable

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

crates/gateway/Cargo.toml

@@ -9,6 +9,7 @@ storaged = { path = "../storaged" }
 catalogd = { path = "../catalogd" }
 queryd = { path = "../queryd" }
 aibridge = { path = "../aibridge" }
+ingestd = { path = "../ingestd" }
 tokio = { workspace = true }
 axum = { workspace = true }
 serde = { workspace = true }