fix(bookmarks): force libsqlite3-sys bundled via explicit feature gate

The chroot build of owlry-2.0.0 failed at link time with every sqlite3_*
symbol undefined — libsqlite3-sys's build.rs was taking the
'build_linked' branch (which links to system libsqlite3) instead of
'build_bundled' (which compiles sqlite3.c statically). The host build
worked only because /usr/lib/libsqlite3.so happens to be installed.

The original Cargo.toml had:

    rusqlite = { version = "0.39", features = ["bundled"], optional = true }

In theory this activates rusqlite/bundled which pulls libsqlite3-sys/bundled.
In practice — apparently a Cargo resolver edge case with optional deps in
edition 2024 — the bundled feature did not flow into the resolved feature
graph in a clean chroot build.

Fixed by declaring rusqlite without inline features and wiring the bundled
flag explicitly in the bookmarks feature row:

    [dependencies]
    rusqlite = { version = "0.39", optional = true }

    [features]
    bookmarks = ["dep:rusqlite", "rusqlite/bundled"]

Verified via 'cargo tree --features full -i libsqlite3-sys -e features':
the libsqlite3-sys 'bundled' feature now traces back to owlry/full ->
owlry/bookmarks -> rusqlite/bundled.

crates/owlry/Cargo.toml

@@ -60,8 +60,11 @@ signal-hook = "0.3"
 expr-solver-lib = "1"
 reqwest = { version = "0.13", default-features = false, features = ["native-tls", "json", "blocking"] }
 
-# Optional providers (gated by cargo features below)
-rusqlite = { version = "0.39", features = ["bundled"], optional = true }
+# Optional providers (gated by cargo features below).
+# Features declared on the bookmarks feature row, not inline here, so the
+# `bundled` flag propagates cleanly to libsqlite3-sys regardless of how
+# downstream consumers compose features.
+rusqlite = { version = "0.39", optional = true }
 
 # Async oneshot channel (background thread -> main loop)
 futures-channel = "0.3"
@@ -81,7 +84,7 @@ dev-logging = []
 
 # Optional providers (compiled in when enabled).
 # The AUR PKGBUILD builds with --features "full" to ship everything.
-bookmarks = ["dep:rusqlite"]
+bookmarks = ["dep:rusqlite", "rusqlite/bundled"]
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