The greedy regexp matching, broken scoring and broken highlight were
sources of frequent complaints about the 'flex' matching style.  This
commit fixes that.

Inspired by the 'hotfuzz' style (available at
https://github.com/axelf4/hotfuzz) it uses a modified version of Gotoh's
1982 dynamic programming algorithm. It is strictly more correct than the
"old" flex.  For example, when matching the pattern 'goto' to no longer
will 'eglot-format' be sorted before some hypothetical much better
'goobarbaz-goto'.  And of course the highlighting is also correctly
placed on the 'goto', not scattered across the candidate.

Regarding performance, it is faster than the naive 'flex', primarily
because of the Elisp rewrite in minibuffer.el.  The matching and costing
algorithm matters but is not the bottleneck.

The Elisp parts of the style were almost completely decoupled from the
pcm/substring styles in lisp/minibuffer.el.  Only
'completion-flex-try-completion' uses some of pcm's code for pattern
augmentation.

* src/minibuf.c (completion--flex-cost-gotoh): New function.

* lisp/minibuffer.el (completion-flex--pattern-str): New variable.
(flex-score-match-tightness): Make obsolete.
(completion--flex-all-completions-1): New helper function.
(completion-flex-try-completion, completion-flex-all-completions): Rewrite.
(completion-substring--all-completions): No longer take transform-pattern-fn.
(completion--flex-adjust-metadata): Tweak.
(completion--flex-score, completion--flex-score-1)
(completion--flex-score-last-md, completion-flex--make-flex-pattern): Delete.

* test/lisp/minibuffer-tests.el (completion--sorted-flex-completions):
New helper function.
(completion-flex-test-non-ascii): New test.
(completion--pcm-score): Delete.
(completion-pcm-test-3, completion-pcm-test-4)
(completion-substring-test-1, completion-substring-test-2)
(completion-flex-test-2, completion-flex-test-3): Tweak.

* etc/NEWS: Describe change.

* lisp/emacs-lisp/package.el (package--autosuggest-install-and-enable)
(package--autosugest-prompt, package-autosuggest): Doc fixes.
* lisp/emacs-lisp/package-activate.el (package-autosuggest-style)
(package-autosuggest-once, package-autosuggest-mode)
(package--suggestion-applies-p)
(package--autosuggest-find-candidates)
(package--autosugest-line-format)
(package--autosuggest-after-change-mode): Fix doc strings and add
:version tags.

* etc/NEWS (bindings):
* doc/emacs/package.texi (Package Installation): Improve wording,
markup and indexing.

* doc/misc/tramp.texi (External packages): Mention also special events.
Emphasise, that Tramp raises remote-file-error.

* etc/NEWS: Tramp signals 'remote-file-error' consequently.
Presentational fixes and improvements.

* lisp/net/tramp.el (tramp-skeleton-process-file)
(tramp-handle-make-symbolic-link, tramp-process-actions)
(tramp-wait-for-regexp, tramp-send-string):
* lisp/net/tramp-adb.el (tramp-adb-get-device)
(tramp-adb-send-command-and-check, tramp-adb-barf-unless-okay)
(tramp-adb-wait-for-output, tramp-adb-maybe-open-connection):
* lisp/net/tramp-archive.el (tramp-archive-handle-not-implemented):
* lisp/net/tramp-crypt.el (tramp-crypt-do-encrypt-or-decrypt-file-name)
(tramp-crypt-do-encrypt-or-decrypt-file):
* lisp/net/tramp-gvfs.el (tramp-gvfs-dbus-event-error)
(tramp-gvfs-maybe-open-connection):
* lisp/net/tramp-sh.el
(tramp-do-directory-files-and-attributes-with-perl)
(tramp-do-copy-or-rename-file-directly)
(tramp-do-copy-or-rename-file-out-of-band)
(tramp-sh-handle-file-local-copy, tramp-sh-handle-write-region)
(tramp-bundle-read-file-names, tramp-maybe-send-script)
(tramp-find-file-exists-command, tramp-barf-if-no-shell-prompt)
(tramp-maybe-open-connection, tramp-wait-for-output)
(tramp-send-command-and-check, tramp-barf-unless-okay)
(tramp-send-command-and-read, tramp-get-ls-command):
* lisp/net/tramp-smb.el (tramp-smb-handle-file-attributes)
(tramp-smb-handle-make-symbolic-link)
(tramp-smb-maybe-open-connection, tramp-smb-call-winexe):
* lisp/net/tramp-sshfs.el (tramp-sshfs-maybe-open-connection):
* lisp/net/tramp-sudoedit.el (tramp-sudoedit-send-command-and-read):
Raise a `remote-file-error' in case of connection problems.

* lisp/net/tramp-rclone.el (tramp-rclone-maybe-open-connection): Improve
check for host.

* lisp/net/tramp-smb.el (tramp-smb-get-localname): Improve error message.

* lisp/net/tramp-sudoedit.el (tramp-default-host-alist):
Set a default for "sudoedit" method.
(tramp-sudoedit-maybe-open-connection): Check for proper host name.
(tramp-sudoedit-send-command): Do not expand ?h.

* lisp/net/tramp.el (tramp-compute-multi-hops): Check for cycle
proxy definition.

* test/lisp/net/tramp-archive-tests.el (tramp-archive-test20-file-modes)
(tramp-archive-test21-file-links): Check for `rmote-file-error'.

* test/lisp/net/tramp-tests.el (tramp-file-name-with-sudo): Declare.
(tramp--test-ignore-make-symbolic-link-error): Check for
`rmote-file-error'.
(tramp-test03-file-name-method-rules): Delete.
(tramp-test03-file-error): New test.
(tramp--test-supports-processes-p): Make it more rebust.

Now that battery--upower-subscribe registers to signals from
DisplayDevice (bug#80229), it is possible to react to more than just
State changes, including Percentage and IsPresent (although the
latter may already be covered by the DeviceAdded and DeviceRemoved
signals).

That means that it should be possible to disable polling via
battery-update-timer and still get timely mode line updates.

* etc/NEWS
(Changes in Specialized Modes and Packages in Emacs 31.1):
Announce new battery-update-interval :type.

* lisp/battery.el (battery-update-interval): Allow setting to nil.
(display-battery-mode): Do not create battery-update-timer then.
(battery-upower-display-device-path): New constant.
(battery--upower-subscribe): Use it.
(battery-upower-subscribe-properties): New variable.
(battery--upower-props-changed): Use it for more flexibility over
which DisplayDevice properties to react to.
(battery--upower-signal-handler): Call battery-update-handler
directly when there is no battery-update-timer.

* lisp/icomplete.el (icomplete-ret): No longer conditionalize on
icomplete-show-matches-on-no-input.
Suggested by Juri Linkov <juri@linkov.net> in bug#62108.
(icomplete-show-matches-on-no-input, icomplete-ret):
* etc/NEWS: Improve documentation.

* src/w32fns.c (w32_register_for_sleep_notifications)
(sleep_notification_callback): Fix signatures.
* src/w32term.h (w32_register_for_sleep_notifications): Fix
prototype.  These changes avoid compilation warnings.

* lisp/system-sleep.el: Remove stray non-ASCII character.

* doc/lispref/os.texi (System Sleep): Remove non-ASCII character,
and fix wording and markup.

* etc/NEWS: Fix wording of recently-added entry.