Fork port: connection architecture + watcher machinery into the substrate (ADR-011/012 §3–§5, task fork-port-connection-watcher)

Kept half of the honker-core fork lands in
alkstore-sqlite/src/substrate/ as schema.rs / watcher.rs / ops.rs
(register D-17): PRAGMA/WAL open posture + set_journal_mode_wal retry,
Writer, Readers, the polling watcher family (SharedUpdateWatcher,
WatcherDeathGuard, stat_identity dead-man's switch), in_savepoint/
UnwindUndo mutation discipline, REAL-coercion arg helpers, notify
scalar + notifications table with the ADR-010 §6 at-attach pruning
cap, stream functions, lock functions.

Port deltas (ADR-012 §4): W-1 bounded reconnect backoff
(MAX_RECONNECT_TICKS=100), W-2 fallible watcher spawn (Result; engine
maps to Database at open in wave 3), dead-man's-switch panic replaced
by log-and-exit through the ordinary death path — death still closes
every subscriber (pinned by test, join now Ok). Table family
_honker_* -> __alkstore_* (D-10); duplicate-column race swallow
re-keyed to pragma_table_info (D-11); scheduler cron_expr -> spec;
fresh-only bootstrap, append-column migrations kept, column-order
equality pinned. Drops confirmed absent: cron, kernel/shm backends,
rate-limit/result tables, superseded queue functions (D-01..D-04).
file-id retained for the kept dead-man's switch (D-18).

43 engine-crate tests green (adapted inherited suites + delta tests +
cross-mechanism pressure); cargo build/clippy -D warnings/fmt clean.
PROVENANCE.md register updated to the landed state (D-01..D-20).

alkstore-sqlite/Cargo.toml

@@ -7,7 +7,16 @@ repository.workspace = true
 
 [dependencies]
 alkstore = { version = "0.1", path = "../alkstore" }
-rusqlite = { version = "0.40", features = ["bundled"] }
+parking_lot = "0.12"
+rusqlite = { version = "0.40", features = ["bundled", "functions"] }
+serde_json = "1"
+thiserror = "2"
+
+# file-id only supports unix and windows. Other targets (WASI, Redox,
+# illumos, etc.) get the `(0, 0)` fallback in substrate::watcher's
+# stat_identity.
+[target.'cfg(any(unix, windows))'.dependencies]
+file-id = "0.2"
 
 [dev-dependencies]
 alkstore-contract-suite = { path = "../alkstore-contract-suite" }