(cherry picked from commit b0759917479ee17ccb11773176dbc8a75323c5cb)
(cherry picked from commit da3f76228e24d2276784ad7e1a03a34d094750e0)
(cherry picked from commit 20d196e74f9d7827cd812e3eb714eb87e888b6db)
(cherry picked from commit 0bf8b1824eac416ddb40fd2e0d7605573ba087a3)
(cherry picked from commit 655bb770a7cf65ada5d3e214ec23219e6cb19df0)
(cherry picked from commit d69d5c2c46f00b041beeb67a6238c5193ce9710a)
(cherry picked from commit 00b55e5a5396a49a6798a3ae2588e412637a77c6)
(cherry picked from commit 456121fd8a4c0c30f7854bd04907f2a0a583d27f)
(cherry picked from commit 9716a158e48ad6333f46fc0806a838603606e5ea)
(cherry picked from commit 7d60a6f5116124b72927a52db0dd36af7a9c3621)
(cherry picked from commit d32a6d9437a38ac35320ad7329eece1ab2bd54d1)
(cherry picked from commit ee1de38527ea1fbd52c319cfbbca24deef951fc1)
(cherry picked from commit 54e7799d13fa041be172d4a05d036cee43e390d4)
(cherry picked from commit 4f04da7ab716ccb1f2816842cde62965e89a852a)
(cherry picked from commit 3e001364ebef3c670e21ed0b7c91a1b4ec8b1577)
(cherry picked from commit d2d5193b388d4b36006a36a5d2145356ff28eec9)
(cherry picked from commit eb1f015c4218c93067f92ab401d6a6973aabf952)
(cherry picked from commit c4587aa893f809dd64418519e2bfc7ebbde4c48f)
Backport #27543 by @wxiaoguang
Fix #27541
The INI package has a quirk: by default, the keys are inherited.
When maintaining the keys, the newly added sub key should not be
affected by the parent key.
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
When users put the secrets into a file (GITEA__sec__KEY__FILE), the
newline sometimes is different to avoid (eg: echo/vim/...)
So the last newline could be removed when reading, it makes the users
easier to maintain the secret files.
Co-authored-by: Giteabot <teabot@gitea.io>
Replace #25580Fix#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.

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 #19857Close#19856Close#10311Close#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