Backport #27914 by @fashberg

This Fixes #27913 

This commit updates `environment-to-ini` to be compatible with update
urfave/cli/v2

Doc: <https://cli.urfave.org/v2/examples/combining-short-options/>

Co-authored-by: Folke <folke@ashberg.de>

Replace #10912

And there are many new tests to cover the CLI behavior

There were some concerns about the "option order in hook scripts"
(https://github.com/go-gitea/gitea/pull/10912#issuecomment-1137543314),
it's not a problem now. Because the hook script uses `/gitea hook
--config=/app.ini pre-receive` format. The "config" is a global option,
it can appear anywhere.

----

## ⚠️ BREAKING ⚠️

This PR does it best to avoid breaking anything. The major changes are:

* `gitea` itself won't accept web's options: `--install-port` / `--pid`
/ `--port` / `--quiet` / `--verbose` .... They are `web` sub-command's
options.
    * Use `./gitea web --pid ....` instead
* `./gitea` can still run the `web` sub-command as shorthand, with
default options
* The sub-command's options must follow the sub-command
* Before: `./gitea --sub-opt subcmd` might equal to `./gitea subcmd
--sub-opt` (well, might not ...)
    * After: only `./gitea subcmd --sub-opt` could be used
    * The global options like `--config` are not affected

Regression of #25648, fix #25924

Test:

```bash
rm -f /tmp/example.ini /tmp/out.ini && \
echo "[security]" > /tmp/example.ini && \
echo "INSTALL_LOCK = true" >> /tmp/example.ini && \
GITEA__foo__bar=1 go run contrib/environment-to-ini/environment-to-ini.go --config=/tmp/example.ini --out=/tmp/out.ini && \
echo "==== example:" && \
cat /tmp/example.ini && \
echo "==== out:" && \
cat /tmp/out.ini
```

Output:

```
2023/07/17 17:40:51 ...nvironment-to-ini.go:99:runEnvironmentToIni() [I] Settings saved to: "/tmp/out.ini"
==== example:
[security]
INSTALL_LOCK = true
==== out:
[security]
INSTALL_LOCK = true

[foo]
bar = 1

```

Replace #25580

Fix #19453

The problem was: when users set "GITEA__XXX__YYY" , the "install page"
doesn't respect it.

So, to make the result consistent and avoid surprising end users, now
the "install page" also writes the environment variables to the config
file.

And, to make things clear, there are enough messages on the UI to tell
users what will happen.

There are some necessary/related changes to `environment-to-ini.go`:

* The "--clear" flag is removed and it was incorrectly written there.
The "clear" operation should be done if INSTALL_LOCK=true
* The "--prefix" flag is removed because it's never used, never
documented and it only causes inconsistent behavior.


![image](https://github.com/go-gitea/gitea/assets/2114189/12778ee4-3fb5-4664-a73a-41ebbd77cd5b)

Fix #25481

The `InitWorkPathAndCommonConfig` calls `LoadCommonSettings` which does
many checks like "current user is root or not".

Some commands like "environment-to-ini" shouldn't do such check, because
it might be run with "root" user at the moment (eg: the docker's setup
script)

ps: in the future, the docker's setup script should be improved to avoid
Gitea's command running with "root"

# The problem

There were many "path tricks":

* By default, Gitea uses its program directory as its work path
* Gitea tries to use the "work path" to guess its "custom path" and
"custom conf (app.ini)"
* Users might want to use other directories as work path
* The non-default work path should be passed to Gitea by GITEA_WORK_DIR
or "--work-path"
* But some Gitea processes are started without these values
    * The "serv" process started by OpenSSH server
    * The CLI sub-commands started by site admin
* The paths are guessed by SetCustomPathAndConf again and again
* The default values of "work path / custom path / custom conf" can be
changed when compiling

# The solution

* Use `InitWorkPathAndCommonConfig` to handle these path tricks, and use
test code to cover its behaviors.
* When Gitea's web server runs, write the WORK_PATH to "app.ini", this
value must be the most correct one, because if this value is not right,
users would find that the web UI doesn't work and then they should be
able to fix it.
* Then all other sub-commands can use the WORK_PATH in app.ini to
initialize their paths.
* By the way, when Gitea starts for git protocol, it shouldn't output
any log, otherwise the git protocol gets broken and client blocks
forever.

The "work path" priority is: WORK_PATH in app.ini > cmd arg --work-path
> env var GITEA_WORK_DIR > builtin default

The "app.ini" searching order is: cmd arg --config > cmd arg "work path
/ custom path" > env var "work path / custom path" > builtin default


## ⚠️ BREAKING

If your instance's "work path / custom path / custom conf" doesn't meet
the requirements (eg: work path must be absolute), Gitea will report a
fatal error and exit. You need to set these values according to the
error log.



----

Close #24818
Close #24222
Close #21606
Close #21498
Close #25107
Close #24981
Maybe close #24503

Replace #23301
Replace #22754

And maybe more

The INI package has many bugs and quirks, and in fact it is
unmaintained.

This PR is the first step for the INI package refactoring: 

* Use Gitea's "config_provider" to provide INI access
* Deprecate the INI package by golangci.yml rule

Replace #19857

Close #19856
Close #10311
Close #10123

Major changes:

1. Move a lot of code from `environment-to-ini.go` to `config_env.go` to
make them testable.
2. Add `__FILE` support
3. Update documents
4. Add tests

Change all license headers to comply with REUSE specification.

Fix #16132

Co-authored-by: flynnnnnnnnnn <flynnnnnnnnnn@github>
Co-authored-by: John Olheiser <john.olheiser@gmail.com>

* Improve install code to avoid low-level mistakes.

If a user tries to do a re-install in a Gitea database, they gets a warning and double check.
When Gitea runs, it never create empty app.ini automatically.

Also some small (related) refactoring:

* Refactor db.InitEngine related logic make it more clean (especially for the install code)
* Move some i18n strings out from setting.go to make the setting.go can be easily maintained.
* Show errors in CLI code if an incorrect app.ini is used.
* APP_DATA_PATH is created when installing, and checked when starting (no empty directory is created any more).

* Remove unnecessary variable assignments

As title

* enable ineffassign

Co-authored-by: zeripath <art27@cantab.net>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

* Only write config in environment-to-ini if there are changes

Only write the new config in environment-to-ini if there are changes or the
destination is not the same as the customconf.

Fix #15719
Fix #15857

Signed-off-by: Andrew Thornton <art27@cantab.net>
Co-authored-by: 6543 <6543@obermui.de>

* Add environment-to-app.ini routine

* Call environment-to-ini in docker setup scripts

* Automatically convert section vars to lower case to match documentation

* Remove git patch instructions

* Add env variable documentation to Install Docker

* Ensure errors from IsDir propagate

* Handle errors when checking IsFile

* Handle and propagate errors from IsExist

* Update modules/templates/static.go

* Update modules/templates/static.go

* Return after ctx.ServerError

* Apply suggestions from code review

* Fix tests

The previous merge managed to break repo_form.go

Signed-off-by: Andrew Thornton <art27@cantab.net>

Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-authored-by: Lauris BH <lauris@nix.lv>

Per 8fe474341f/deprecated.go (L24)

* Add contrib/environment-to-ini

This contrib command provides a mechanism to allow arbitrary setting
of ini values using the environment variable in a more docker standard
fashion.

Environment variable keys should be structured as:

"GITEA__SECTION_NAME__KEY_NAME"

Use of the command is explained in the README.

Partial fix for #350
Closes #7287

* Update contrib/environment-to-ini/environment-to-ini.go

Co-Authored-By: 6543 <6543@obermui.de>

Co-authored-by: Antoine GIRARD <sapk@users.noreply.github.com>
Co-authored-by: 6543 <6543@obermui.de>