p2: digest with in-sift FIFO, SQLite caches, Honcho context, recover

Dixie is capped (max_inflight 2, queue_depth 8, queue_wait 20s) and
never queued on llama-server. Streaming chat, thinking off, 45s
fallback to clean. Digest and chunk-embedding caches are
content-addressed SQLite (Honcho context is not cached). Recover
uses the guarded Fetcher. guardian-star is refused in code.

vendor/modernc.org/sqlite/lib/sqlite_g_0000000000003eec.go

@@ -0,0 +1,33 @@
+// Code generated by modernc.org/undup from the per-target sqlite_*.go files; DO NOT EDIT.
+
+//go:build (freebsd && 386) || (freebsd && amd64) || (freebsd && arm64) || (linux && 386) || (linux && amd64) || (linux && arm64) || (linux && loong64) || (linux && ppc64le) || (linux && riscv64) || (linux && s390x)
+
+package sqlite3
+
+// C documentation
+//
+//	/*
+//	** The unixFile structure is subclass of sqlite3_file specific to the unix
+//	** VFS implementations.
+//	*/
+type TunixFile = struct {
+	FpMethod               uintptr
+	FpVfs                  uintptr
+	FpInode                uintptr
+	Fh                     int32
+	FeFileLock             uint8
+	FctrlFlags             uint16
+	FlastErrno             int32
+	FlockingContext        uintptr
+	FpPreallocatedUnused   uintptr
+	FzPath                 uintptr
+	FpShm                  uintptr
+	FszChunk               int32
+	FnFetchOut             int32
+	FmmapSize              Tsqlite3_int64
+	FmmapSizeActual        Tsqlite3_int64
+	FmmapSizeMax           Tsqlite3_int64
+	FpMapRegion            uintptr
+	FsectorSize            int32
+	FdeviceCharacteristics int32
+}