Rename doc/manual{src -> source}

This is needed to avoid this
https://github.com/mesonbuild/meson/issues/13774 when we go back to
making our subproject directory `src`.

doc/manual/source/command-ref/nix-store/dump.md

@@ -0,0 +1,41 @@
+# Name
+
+`nix-store --dump` - write a single path to a [Nix Archive]
+
+## Synopsis
+
+`nix-store` `--dump` *path*
+
+## Description
+
+The operation `--dump` produces a [Nix archive](@docroot@/glossary.md#gloss-nar) (NAR) file containing the
+contents of the file system tree rooted at *path*. The archive is
+written to standard output.
+
+A NAR archive is like a TAR or Zip archive, but it contains only the
+information that Nix considers important. For instance, timestamps are
+elided because all files in the Nix store have their timestamp set to 0
+anyway. Likewise, all permissions are left out except for the execute
+bit, because all files in the Nix store have 444 or 555 permission.
+
+Also, a NAR archive is *canonical*, meaning that “equal” paths always
+produce the same NAR archive. For instance, directory entries are
+always sorted so that the actual on-disk order doesn’t influence the
+result.  This means that the cryptographic hash of a NAR dump of a
+path is usable as a fingerprint of the contents of the path. Indeed,
+the hashes of store paths stored in Nix’s database (see `nix-store --query
+--hash`) are SHA-256 hashes of the NAR dump of each store path.
+
+NAR archives support filenames of unlimited length and 64-bit file
+sizes. They can contain regular files, directories, and symbolic links,
+but not other types of files (such as device nodes).
+
+A Nix archive can be unpacked using [`nix-store --restore`](@docroot@/command-ref/nix-store/restore.md).
+
+[Nix Archive]: @docroot@/store/file-system-object/content-address.md#serial-nix-archive
+
+{{#include ./opt-common.md}}
+
+{{#include ../opt-common.md}}
+
+{{#include ../env-common.md}}