Merge recent fixes from trunk.  Cherrypick of [c43b59dac1], [a221aa82bb], [e1eba1fb09], and [1e131094b5].

FossilOrigin-Name: c697d2f83c2d8ea0a100b84b0debb6a322c3a876

• manifest[diff]
• manifest.uuid[diff]
• src/main.c[diff]
• src/os_unix.c[diff]
• src/os_win.c[diff]
• src/random.c[diff]
• src/sqlite.h.in[diff]
• src/sqliteInt.h[diff]
• test/win32longpath.test[diff]