Added compatibility WAL flags for Global.Settings

Added Settings.Global.SQLITE_COMPATIBILITY_WAL_FLAGS -
configuration flags for SQLite Compatibility WAL. Encoded as a key-value
list, separated by commas. E.g.:
compatibility_wal_supported=true, wal_syncmode=OFF

SQLiteCompatibilityWalFlags caches the value of
SQLITE_COMPATIBILITY_WAL_FLAGS on first access and keeps it through
the lifetime of the process for consistent behavior across all
connections.

Test: SQLiteCompatibilityWalFlagsTest
Test: setting put global ... + verify that dumpsys dbinfo has the new flag
Bug: 70226732
Bug: 70517616
Change-Id: Ifacbf5908c83351ebe5dea676eeb716af039fb14